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$$ \beta=2 \pi c \tilde{\omega}_{\mathrm{obs}}\left(\frac{\mu}{2 D}\right)^{1 / 2} $$ Given that $\tilde{\omega}_{\mathrm{obs}}=2886 \mathrm{~cm}^{-1}$ and $D=440.2 \mathrm{~kJ} \cdot \mathrm{mol}^{-1}$ for $\mathrm{H}^{35} \mathrm{Cl}$, calculate $\beta$.
1.81
1.81
5-10
$10^{10} \mathrm{~m}^{-1}$
chemmc
Two narrow slits separated by $0.10 \mathrm{~mm}$ are illuminated by light of wavelength $600 \mathrm{~nm}$. If a detector is located $2.00 \mathrm{~m}$ beyond the slits, what is the distance between the central maximum and the first maximum?
12
12
1-44
mm
chemmc
$$ \text { If we locate an electron to within } 20 \mathrm{pm} \text {, then what is the uncertainty in its speed? } $$
3.7
3.7
1-46
$10^7 \mathrm{~m} \cdot \mathrm{s}^{-1}$
chemmc
The mean temperature of the earth's surface is $288 \mathrm{~K}$. What is the maximum wavelength of the earth's blackbody radiation?
1.01
1.01
1-14
10^{-5} \mathrm{~m}
chemmc
The power output of a laser is measured in units of watts (W), where one watt is equal to one joule per second. $\left(1 \mathrm{~W}=1 \mathrm{~J} \cdot \mathrm{s}^{-1}\right.$.) What is the number of photons emitted per second by a $1.00 \mathrm{~mW}$ nitrogen laser? The wavelength emitted by a nitrogen laser is $337 ...
1.70
1.70
1-16
$ 10^{15} \text { photon } \cdot \mathrm{s}^{-1} $
chemmc
Sirius, one of the hottest known stars, has approximately a blackbody spectrum with $\lambda_{\max }=260 \mathrm{~nm}$. Estimate the surface temperature of Sirius.
11000
11000
1-7
$\mathrm{~K}$
chemmc
A ground-state hydrogen atom absorbs a photon of light that has a wavelength of $97.2 \mathrm{~nm}$. It then gives off a photon that has a wavelength of $486 \mathrm{~nm}$. What is the final state of the hydrogen atom?
2
no units
2
1-26
chemmc
It turns out that the solution of the Schrödinger equation for the Morse potential can be expressed as $$ G(v)=\tilde{\omega}_{\mathrm{e}}\left(v+\frac{1}{2}\right)-\tilde{\omega}_{\mathrm{e}} \tilde{x}_{\mathrm{e}}\left(v+\frac{1}{2}\right)^2 $$ The Harmonic Oscillator and Vibrational Spectroscopy where $$ \til...
0.01961
only first part taken of the question
0.01961
5-12
chemmc
In the infrared spectrum of $\mathrm{H}^{127} \mathrm{I}$, there is an intense line at $2309 \mathrm{~cm}^{-1}$. Calculate the force constant of $\mathrm{H}^{127} \mathrm{I}$.
313
313
5-13
$ \mathrm{~N} \cdot \mathrm{m}^{-1}$
chemmc
Calculate the percentage difference between $e^x$ and $1+x$ for $x=0.0050$
1.25
Math Part D (after chapter 4)
1.25
D-1
$10^{-3} \%$
chemmc
Calculate the kinetic energy of an electron in a beam of electrons accelerated by a voltage increment of $100 \mathrm{~V}$
1.602
1.602
1-39
$10^{-17} \mathrm{~J} \cdot$ electron ${ }^{-1}$
chemmc
We must first convert $\phi$ from electron volts to joules. $$ \begin{aligned} \phi & =2.28 \mathrm{eV}=(2.28 \mathrm{eV})\left(1.602 \times 10^{-19} \mathrm{~J} \cdot \mathrm{eV}^{-1}\right) \\ & =3.65 \times 10^{-19} \mathrm{~J} \end{aligned} $$ Using Equation $h v_0=\phi$, we have $$ v_0=\frac{3.65 \times ...
Given that the work function for sodium metal is $2.28 \mathrm{eV}$, what is the threshold frequency $v_0$ for sodium?
5.51
5.51
1.1_3
$10^{14}\mathrm{~Hz}$
chemmc
The mass of an electron is $9.109 \times 10^{-31} \mathrm{~kg}$. One percent of the speed of light is $$ v=(0.0100)\left(2.998 \times 10^8 \mathrm{~m} \cdot \mathrm{s}^{-1}\right)=2.998 \times 10^6 \mathrm{~m} \cdot \mathrm{s}^{-1} $$ The momentum of the electron is given by $$ \begin{aligned} p=m_{\mathrm{e}} v...
Calculate the de Broglie wavelength of an electron traveling at $1.00 \%$ of the speed of light.
243
243
1.1_11
$\mathrm{pm}$
chemmc
Because $u(\theta, \phi)$ is independent of $r$, we start with $$ \nabla^2 u=\frac{1}{r^2 \sin \theta} \frac{\partial}{\partial \theta}\left(\sin \theta \frac{\partial u}{\partial \theta}\right)+\frac{1}{r^2 \sin ^2 \theta} \frac{\partial^2 u}{\partial \phi^2} $$ Substituting $$ u(\theta, \phi)=-\left(\frac{3}{8 ...
Show that $u(\theta, \phi)=Y_1^1(\theta, \phi)$ given in Example $$ \begin{aligned} &Y_1^1(\theta, \phi)=-\left(\frac{3}{8 \pi}\right)^{1 / 2} e^{i \phi} \sin \theta\\ &Y_1^{-1}(\theta, \phi)=\left(\frac{3}{8 \pi}\right)^{1 / 2} e^{-i \phi} \sin \theta \end{aligned} $$ satisfies the equation $\nabla^2 u=\frac{c}{r^2} u...
-2
-2
E.E_4
chemmc
We want to find the constant $c$ such that $$ I=c^2\left\langle\Psi_2(1,2) \mid \Psi_2(1,2)\right\rangle=1 $$ First notice that $\Psi_2(1,2)$ can be factored into the product of a spatial part and a spin part: $$ \begin{aligned} \Psi_2(1,2) & =1 s(1) 1 s(2)[\alpha(1) \beta(2)-\alpha(2) \beta(1)] \\ & =1 s\left(...
The wave function $\Psi_2(1,2)$ given by Equation 9.39 is not normalized as it stands. Determine the normalization constant of $\Psi_2(1,2)$ given that the "1s" parts are normalized.
$1 / \sqrt{2}$
0.70710678
9.9_4
chemmc
The equations for $c_1$ and $c_2$ associated with Equation $$ \left|\begin{array}{ll} H_{11}-E S_{11} & H_{12}-E S_{12} \\ H_{12}-E S_{12} & H_{22}-E S_{22} \end{array}\right|=0 $$ are $$ c_1(\alpha-E)+c_2 \beta=0 \quad \text { and } \quad c_1 \beta+c_2(\alpha-E)=0 $$ For $E=\alpha+\beta$, either equation yields $...
Find the bonding and antibonding Hückel molecular orbitals for ethene.
$1 / \sqrt{2}$
0.70710678
11.11_11
chemmc
Letting $\xi=\alpha^{1 / 2} x$ in Table 5.3 , we have $$ \begin{aligned} & \psi_0(\xi)=\left(\frac{\alpha}{\pi}\right)^{1 / 4} e^{-\xi^2 / 2} \\ & \psi_1(\xi)=\sqrt{2}\left(\frac{\alpha}{\pi}\right)^{1 / 4} \xi e^{-\xi^2 / 2} \\ & \psi_2(\xi)=\frac{1}{\sqrt{2}}\left(\frac{\alpha}{\pi}\right)^{1 / 4}\left(2 \xi^2-1...
Using the explicit formulas for the Hermite polynomials given in Table 5.3 as below $$ \begin{array}{ll} H_0(\xi)=1 & H_1(\xi)=2 \xi \\ H_2(\xi)=4 \xi^2-2 & H_3(\xi)=8 \xi^3-12 \xi \\ H_4(\xi)=16 \xi^4-48 \xi^2+12 & H_5(\xi)=32 \xi^5-160 \xi^3+120 \xi \end{array} $$, show that a $0 \rightarrow 1$ vibrational transition...
0
0
5.5_12
chemmc
According to Equation $$ \begin{aligned} &v_{\mathrm{obs}}=2 B(J+1) \quad J=0,1,2, \ldots\\ &B=\frac{h}{8 \pi^2 I} \end{aligned} $$, the spacing of the lines in the microwave spectrum of $\mathrm{H}^{35} \mathrm{Cl}$ is given by $$ 2 B=\frac{h}{4 \pi^2 I} $$ $$ \frac{h}{4 \pi^2 I}=6.26 \times 10^{11} \mathrm{~H...
To a good approximation, the microwave spectrum of $\mathrm{H}^{35} \mathrm{Cl}$ consists of a series of equally spaced lines, separated by $6.26 \times 10^{11} \mathrm{~Hz}$. Calculate the bond length of $\mathrm{H}^{35} \mathrm{Cl}$.
129
129
6.6_2
$\mathrm{pm}$
chemmc
To find $1 E_{\mathrm{h}}$ expressed in joules, we substitute the SI values of $m_{\mathrm{e}}, e$, $4 \pi \epsilon_0$, and $\hbar$ into the above equation. Using these values from Table $$$ \begin{array}{lll} \hline \text { Property } & \text { Atomic unit } & \text { SI equivalent } \\ \hline \text { Mass } & \text ...
The unit of energy in atomic units is given by $$ 1 E_{\mathrm{h}}=\frac{m_{\mathrm{e}} e^4}{16 \pi^2 \epsilon_0^2 \hbar^2} $$ Express $1 E_{\mathrm{h}}$ in electron volts $(\mathrm{eV})$.
27.211
27.211
9.9_1
$\mathrm{eV}$
chemmc
The probability that the particle will be found between 0 and $a / 2$ is $$ \operatorname{Prob}(0 \leq x \leq a / 2)=\int_0^{a / 2} \psi^*(x) \psi(x) d x=\frac{2}{a} \int_0^{a / 2} \sin ^2 \frac{n \pi x}{a} d x $$ If we let $n \pi x / a$ be $z$, then we find $$ \begin{aligned} \operatorname{Prob}(0 \leq x \leq...
Calculate the probability that a particle in a one-dimensional box of length $a$ is found between 0 and $a / 2$.
$\frac{1}{2}$
0.5
3.3_6
chemmc
An automobile with a mass of $1000 \mathrm{~kg}$, including passengers, settles $1.0 \mathrm{~cm}$ closer to the road for every additional $100 \mathrm{~kg}$ of passengers. It is driven with a constant horizontal component of speed $20 \mathrm{~km} / \mathrm{h}$ over a washboard road with sinusoidal bumps. The amplitu...
-0.16
-0.16
Problem 3.40
$ \mathrm{~mm}$
class
Find the shortest path between the $(x, y, z)$ points $(0,-1,0)$ and $(0,1,0)$ on the conical surface $z=1-\sqrt{x^2+y^2}$. What is the length of the path? Note: this is the shortest mountain path around a volcano.
$2 \sqrt{2} \sin \frac{\pi}{2 \sqrt{2}}$
2.534324263
Problem 6.14
class
In the blizzard of ' 88 , a rancher was forced to drop hay bales from an airplane to feed her cattle. The plane flew horizontally at $160 \mathrm{~km} / \mathrm{hr}$ and dropped the bales from a height of $80 \mathrm{~m}$ above the flat range. She wanted the bales of hay to land $30 \mathrm{~m}$ behind the cattle so as...
210
210
Problem 2.6
$\mathrm{~m}$
class
Consider a damped harmonic oscillator. After four cycles the amplitude of the oscillator has dropped to $1 / e$ of its initial value. Find the ratio of the frequency of the damped oscillator to its natural frequency.
$\frac{8 \pi}{\sqrt{64 \pi^2+1}}$
0.9992093669
Problem 3.44
class
What is the minimum escape velocity of a spacecraft from the moon?
2380
2380
Problem 8.28
$\mathrm{~m} / \mathrm{s}$
class
A rocket has an initial mass of $7 \times 10^4 \mathrm{~kg}$ and on firing burns its fuel at a rate of 250 $\mathrm{kg} / \mathrm{s}$. The exhaust velocity is $2500 \mathrm{~m} / \mathrm{s}$. If the rocket has a vertical ascent from resting on the earth, how long after the rocket engines fire will the rocket lift off?
25
25
Problem 9.60
$\mathrm{~s}$
class
A spacecraft of mass $10,000 \mathrm{~kg}$ is parked in a circular orbit $200 \mathrm{~km}$ above Earth's surface. What is the minimum energy required (neglect the fuel mass burned) to place the satellite in a synchronous orbit (i.e., $\tau=24 \mathrm{hr}$ )?
2.57
2.57
Problem 8.42
$10^{11} \mathrm{~J}$
class
A clown is juggling four balls simultaneously. Students use a video tape to determine that it takes the clown $0.9 \mathrm{~s}$ to cycle each ball through his hands (including catching, transferring, and throwing) and to be ready to catch the next ball. What is the minimum vertical speed the clown must throw up each ba...
13.2
13.2
Problem 2.4
$\mathrm{~m} \cdot \mathrm{s}^{-1}$
class
A deuteron (nucleus of deuterium atom consisting of a proton and a neutron) with speed $14.9 \mathrm{~km} / \mathrm{s}$ collides elastically with a neutron at rest. Use the approximation that the deuteron is twice the mass of the neutron. If the deuteron is scattered through a $\mathrm{LAB}$ angle $\psi=10^{\circ}$, wh...
14.44
14.44
Problem 9.22
$\mathrm{~km} / \mathrm{s}$
class
A student drops a water-filled balloon from the roof of the tallest building in town trying to hit her roommate on the ground (who is too quick). The first student ducks back but hears the water splash $4.021 \mathrm{~s}$ after dropping the balloon. If the speed of sound is $331 \mathrm{~m} / \mathrm{s}$, find the heig...
71
71
Problem 2.30
$\mathrm{~m}$
class
A steel ball of velocity $5 \mathrm{~m} / \mathrm{s}$ strikes a smooth, heavy steel plate at an angle of $30^{\circ}$ from the normal. If the coefficient of restitution is 0.8 , at what velocity does the steel ball bounce off the plate?
$4.3$
4.3
Problem 9.42
$\mathrm{~m} / \mathrm{s}$
class
Include air resistance proportional to the square of the ball's speed in the previous problem. Let the drag coefficient be $c_W=0.5$, the softball radius be $5 \mathrm{~cm}$ and the mass be $200 \mathrm{~g}$. Find the initial speed of the softball needed now to clear the fence.
35.2
35.2
Problem 2.18
$\mathrm{~m} \cdot \mathrm{s}^{-1}$
class
A child slides a block of mass $2 \mathrm{~kg}$ along a slick kitchen floor. If the initial speed is 4 $\mathrm{m} / \mathrm{s}$ and the block hits a spring with spring constant $6 \mathrm{~N} / \mathrm{m}$, what is the maximum compression of the spring?
2.3
2.3
Problem 2.26
$\mathrm{~m}$
class
An Earth satellite has a perigee of $300 \mathrm{~km}$ and an apogee of $3,500 \mathrm{~km}$ above Earth's surface. How far is the satellite above Earth when it has rotated $90^{\circ}$ around Earth from perigee?
1590
1590
Problem 8.24
$\mathrm{~km}$
class
Two masses $m_1=100 \mathrm{~g}$ and $m_2=200 \mathrm{~g}$ slide freely in a horizontal frictionless track and are connected by a spring whose force constant is $k=0.5 \mathrm{~N} / \mathrm{m}$. Find the frequency of oscillatory motion for this system.
2.74
2.74
Problem 3.6
$\mathrm{rad} \cdot \mathrm{s}^{-1}$
class
Calculate the minimum $\Delta v$ required to place a satellite already in Earth's heliocentric orbit (assumed circular) into the orbit of Venus (also assumed circular and coplanar with Earth). Consider only the gravitational attraction of the Sun.
5275
5275
Problem 8.38
$\mathrm{~m} / \mathrm{s}$
class
A potato of mass $0.5 \mathrm{~kg}$ moves under Earth's gravity with an air resistive force of $-k m v$. Find the terminal velocity if the potato is released from rest and $k=$ $0.01 \mathrm{~s}^{-1}$.
1000
1000
Problem 2.54
$\mathrm{~m} / \mathrm{s}$
class
The height of a hill in meters is given by $z=2 x y-3 x^2-4 y^2-18 x+28 y+12$, where $x$ is the distance east and $y$ is the distance north of the origin. What is the $x$ distance of the top of the hill?
-2
-2
Problem 1.40
m
class
Shot towers were popular in the eighteenth and nineteenth centuries for dropping melted lead down tall towers to form spheres for bullets. The lead solidified while falling and often landed in water to cool the lead bullets. Many such shot towers were built in New York State. Assume a shot tower was constructed at lati...
2.26
2.26
Problem 10.22
$\mathrm{~mm}$
class
A simple harmonic oscillator consists of a 100-g mass attached to a spring whose force constant is $10^4 \mathrm{dyne} / \mathrm{cm}$. The mass is displaced $3 \mathrm{~cm}$ and released from rest. Calculate the natural frequency $\nu_0$.
6.9
6.9
Problem 3.2
$10^{-2} \mathrm{~s}^{-1}$
class
Use the function described in Example 4.3, $x_{n+1}=\alpha x_n\left(1-x_n^2\right)$ where $\alpha=2.5$. Consider two starting values of $x_1$ that are similar, 0.9000000 and 0.9000001 . Determine the lowest value of $n$ for which the two values diverge by more than $30 \%$.
30
30
Problem 4.14
class
A gun fires a projectile of mass $10 \mathrm{~kg}$ of the type to which the curves of Figure 2-3 apply. The muzzle velocity is $140 \mathrm{~m} / \mathrm{s}$. Through what angle must the barrel be elevated to hit a target on the same horizontal plane as the gun and $1000 \mathrm{~m}$ away? Compare the results with thos...
17.4
17.4
Problem 2.20
$^{\circ}$
class
A spacecraft is placed in orbit $200 \mathrm{~km}$ above Earth in a circular orbit. Calculate the minimum escape speed from Earth.
3.23
3.23
Problem 8.30
$ \mathrm{~km} / \mathrm{s}$
class
Find the value of the integral $\int_S(\nabla \times \mathbf{A}) \cdot d \mathbf{a}$ if the vector $\mathbf{A}=y \mathbf{i}+z \mathbf{j}+x \mathbf{k}$ and $S$ is the surface defined by the paraboloid $z=1-x^2-y^2$, where $z \geq 0$.
$-\pi$
-3.141592
Problem 1.38
class
A skier weighing $90 \mathrm{~kg}$ starts from rest down a hill inclined at $17^{\circ}$. He skis $100 \mathrm{~m}$ down the hill and then coasts for $70 \mathrm{~m}$ along level snow until he stops. Find the coefficient of kinetic friction between the skis and the snow.
0.18
0.18
Problem 2.24
class
Consider a comet moving in a parabolic orbit in the plane of Earth's orbit. If the distance of closest approach of the comet to the $\operatorname{Sun}$ is $\beta r_E$, where $r_E$ is the radius of Earth's (assumed) circular orbit and where $\beta<1$, show that the time the comet spends within the orbit of Earth is giv...
76
76
Problem 8.12
$ \text { days }$
class
A British warship fires a projectile due south near the Falkland Islands during World War I at latitude $50^{\circ} \mathrm{S}$. If the shells are fired at $37^{\circ}$ elevation with a speed of $800 \mathrm{~m} / \mathrm{s}$, by how much do the shells miss their target?
260
260
Problem 10.18
$\mathrm{~m}$
class
Two double stars of the same mass as the sun rotate about their common center of mass. Their separation is 4 light years. What is their period of revolution?
9
9
Problem 8.46
$10^7 \mathrm{yr}$
class
To perform a rescue, a lunar landing craft needs to hover just above the surface of the moon, which has a gravitational acceleration of $g / 6$. The exhaust velocity is $2000 \mathrm{~m} / \mathrm{s}$, but fuel amounting to only 20 percent of the total mass may be used. How long can the landing craft hover?
273
273
Problem 9.62
$\mathrm{~s}$
class
In an elastic collision of two particles with masses $m_1$ and $m_2$, the initial velocities are $\mathbf{u}_1$ and $\mathbf{u}_2=\alpha \mathbf{u}_1$. If the initial kinetic energies of the two particles are equal, find the conditions on $u_1 / u_2$ such that $m_1$ is at rest after the collision and $\alpha$ is positi...
$3 \pm 2 \sqrt{2}$
5.828427125
Problem 9.36
class
Astronaut Stumblebum wanders too far away from the space shuttle orbiter while repairing a broken communications satellite. Stumblebum realizes that the orbiter is moving away from him at $3 \mathrm{~m} / \mathrm{s}$. Stumblebum and his maneuvering unit have a mass of $100 \mathrm{~kg}$, including a pressurized tank of...
11
11
Problem 9.12
$ \mathrm{~m} / \mathrm{s}$
class
null
A deuteron (nucleus of deuterium atom consisting of a proton and a neutron) with speed $14.9$ km / s collides elastically with a neutron at rest. Use the approximation that the deuteron is twice the mass of the neutron. If the deuteron is scattered through a LAB angle $\psi = 10^\circ$, the final speed of the deuteron ...
$74.8^\circ$, $5.2^\circ$
30
9.22 B.
$^\circ$
class
null
A steel ball of velocity $5$ m/s strikes a smooth, heavy steel plate at an angle of $30^\circ$ from the normal. If the coefficient of restitution is 0.8, at what angle from the normal does the steel ball bounce off the plate?
$36^\circ$
36
9.42 B.
$^\circ$
class
null
A string is set into motion by being struck at a point $L/4$ from one end by a triangular hammer. The initial velocity is greatest at $x = L/4$ and decreases linearly to zero at $x = 0$ and $x = L/2$. The region $L/2 \leq x \leq L$ is initially undisturbed. Determine the subsequent motion of the string. How many decibe...
4.4, 13.3
4.4
13.6
dB
class
null
In the blizzard of ' 88 , a rancher was forced to drop hay bales from an airplane to feed her cattle. The plane flew horizontally at $160 \mathrm{~km} / \mathrm{hr}$ and dropped the bales from a height of $80 \mathrm{~m}$ above the flat range. To not hit the cattle, what is the largest time error she could make while p...
0.68
0.68
2.6 B.
seconds
class
null
A free neutron is unstable and decays into a proton and an electron. How much energy other than the rest energies of the proton and electron is available if a neutron at rest decays? (This is an example of nuclear beta decay. Another particle, called a neutrino-- actually an antineutrino $\bar v$ is also produced.)
0.8
0.8
14.30
$MeV$
class
null
A new single-stage rocket is developed in the year 2023, having a gas exhaust velocity of $4000$ m/s. The total mass of the rocket is $10^5$ kg, with $90$% of its mass being fuel. The fuel burns quickly in $100$ s at a constant rate. For testing purposes, the rocket is launched vertically at rest from Earth's surface. ...
950
950
9.64 C.
km
class
null
Calculate the effective gravitational field vector $g$ at Earth's surface at the poles. Take account of the difference in the equatorial (6378 km) and polar (6357 km) radius as well as the centrifugal force. How well does the result agree with the difference calculated with the result $g = 9.780356[1 + 0.0052885sin^2\l...
9.832
9.832
10.20
$m/s^2$
class
null
In nuclear and particle physics, momentum is usually quoted in $MeV / c$ to facilitate calculations. Calculate the kinetic energy of an electron if it has a momentum of $1000$ $MeV/c$
$T_{electron} = 999.5$, $T_{proton} = 433$
999.5
14.32
$MeV$
class
null
A skier weighing $90$ kg starts from rest down a hill inclined at $17^\circ$. He skis 100 m down the hill and then coasts for 70 m along level snow until he stops. Given a coefficient of kinetic friction of $\mu_k = 0.18$, what velocity does the skier have at the bottom of the hill?
15.6
Uses answer from part A. (coefficient of kinetic friction)
15.6
2.24 B.
$m/s$
class
null
A rocket starts from rest in free space by emitting mass. At what fraction of the initial mass is the momentum a maximum?
$e^{-1}$
0.367879
9.54
class
null
A particle moves in a plane elliptical orbit described by the position vector $r = 2b \sin \omega ti + b \cos \omega tj$ What is the angle between $v$ and $a$ at time $t = \frac{\pi}{2\omega}$ ?
$90^\circ$
90
1.10 B.
$^\circ$
class
null
An Earth satellite has a perigee of $300$ km and an apogee of $3,500$ km above Earth's surface. How far is the satellite above Earth when it has moved halfway from perigee to apogee?
1900
1900
8.24 (b)
$km$
class
null
In a typical model rocket (Estes Alpha III) the Estes C6 solid rocket engine provides a total impulse of $8.5$ N-s. Assume the total rocket mass at launch is $54$ g and that it has a rocket engine of mass $20$ g that burns evenly for $1.5$ s. The rocket diameter is $24$ mm. Assume a constant burn rate of the propellent...
108
108
9.66 B.
m
class
null
A deuteron (nucleus of deuterium atom consisting of a proton and a neutron) with speed $14.9$ km / s collides elastically with a neutron at rest. Use the approximation that the deuteron is twice the mass of the neutron. If the deuteron is scattered through a LAB angle $\psi = 10^\circ$, what is the final speed of the n...
5.18
9.22 A, but only the neutron (not deuteron, which has already been annotated)
5.18
9.22 A.
km / s
class
null
A new single-stage rocket is developed in the year 2023, having a gas exhaust velocity of $4000$ m/s. The total mass of the rocket is $10^5$ kg, with $90$% of its mass being fuel. The fuel burns quickly in $100$ s at a constant rate. For testing purposes, the rocket is launched vertically at rest from Earth's surface. ...
890
890
9.64 B.
km
class
null
A new single-stage rocket is developed in the year 2023, having a gas exhaust velocity of $4000$ m/s. The total mass of the rocket is $10^5$ kg, with $90$% of its mass being fuel. The fuel burns quickly in $100$ s at a constant rate. For testing purposes, the rocket is launched vertically at rest from Earth's surface. ...
8900
8900
9.64 D.
km
class
null
A racer attempting to break the land speed record rockets by two markers spaced $100$ m apart on the ground in a time of $0.4$ $\mu s$ as measured by an observer on the ground. How far apart do the two markers appear to the racer?
55.3
Omitted the last two questions / answers
55.3
14.12
$m$
class
null
A billiard ball of intial velocity $u_1$ collides with another billard ball (same mass) initially at rest. The first ball moves off at $\psi = 45^\circ$. For an elastic collision, say the velocities of both balls after the collision is $v_1 = v_2 = \frac{u_1}{\sqrt(2)}$. At what LAB angle does the second ball emerge?
45
45
9.34 B.
$^\circ$
class
null
Calculate the effective gravitational field vector $\textbf{g}$ at Earth's surface at the equator. Take account of the difference in the equatorial (6378 km) and polar (6357 km) radius as well as the centrifugal force.
9.780
Only calculating the equator, not the polar.
9.780
10.20 B.
$m/s^2$
class
null
An astronaut travels to the nearest star system, 4 light years away, and returns at a speed $0.3c$. How much has the astronaut aged relative to those people remaining on Earth?
25.4
Astronaut ages 25.4, people on Earth age 26.7
25.4
14.20
years
class
null
In a typical model rocket (Estes Alpha III) the Estes C6 solid rocket engine provides a total impulse of $8.5$ N-s. Assume the total rocket mass at launch is $54$ g and that it has a rocket engine of mass $20$ g that burns evenly for $1.5$ s. The rocket diameter is $24$ mm. Assume a constant burn rate of the propellent...
131
131
9.66 A.
m/s
class
null
A new single-stage rocket is developed in the year 2023, having a gas exhaust velocity of $4000$ m/s. The total mass of the rocket is $10^5$ kg, with $90$% of its mass being fuel. The fuel burns quickly in $100$ s at a constant rate. For testing purposes, the rocket is launched vertically at rest from Earth's surface. ...
3700
3700
9.64 A.
km
class
null
Include air resistance proportional to the square of the ball's speed in the previous problem. Let the drag coefficient be $c_w = 0.5$, the softball radius be $5$ cm and the mass be $200$ g. Given a speed of 35.2 m/s, find the initial elevation angle that allows the ball to most easily clear the fence.
$40.7^\circ$
Used answer given in part A. for speed
40.7
2.18 B.
$^\circ$
class
null
Show that the small angular deviation of $\epsilon$ of a plumb line from the true vertical (i.e., toward the center of Earth) at a point on Earth's surface at a latitude $\lambda$ is $\epsilon = \frac{R\omega^2sin\lambda cos\lambda}{g_0 - R\omega^2 cos^2\lambda}$ where R is the radius of Earth. What is the value (in se...
6
6
10.12
min
class
null
A potato of mass 0.5 kg moves under Earth's gravity with an air resistive force of -$kmv$. The terminal velocity of the potato when released from rest is $v = 1000$ m/s, with $k=0.01s^{-1}$. Find the maximum height of the potato if it has the same value of k, but it is initially shot directly upward with a student-made...
680
Used terminal velocity answer of 1000 m/s from part A.
680
2.54 B.
$m$
class
The static frictional force has the approximate maximum value$$f_{\max }=\mu_s N$$ Then we have, $y$-direction $$ -F_g \cos \theta+N=0 $$ $x$-direction $$ -f_s+F_g \sin \theta=m \ddot{x} $$ The static frictional force $f_s$ will be some value $f_s \leq f_{\max }$ required to keep $\ddot{x}=0$ -that is, to keep...
If the coefficient of static friction between the block and plane in the previous example is $\mu_s=0.4$, at what angle $\theta$ will the block start sliding if it is initially at rest?
22
22
2.2
$^{\circ}$
class
The Equation $\tau^2=\frac{4 \pi^2 a^3}{G(m_1+m_2)} \cong \frac{4 \pi^2 a^3}{G m_2}$ relates the period of motion with the semimajor axes. Because $m$ (Halley's comet) $\ll m_{\text {Sun }}$ $$ \begin{aligned} a & =\left(\frac{G m_{\text {Sun }} \tau^2}{4 \pi^2}\right)^{1 / 3} \\ & =\left[\frac{\left.\left(6.67 \t...
Halley's comet, which passed around the sun early in 1986, moves in a highly elliptical orbit with an eccentricity of 0.967 and a period of 76 years. Calculate its minimum distances from the Sun.
8.8
8.8
8.4
$10^{10} \mathrm{m}$
class
Using $\mathbf{F}=m \mathrm{~g}$, the force components become $x$-direction $$ 0=m \ddot{x} $$ y-direction $-m g=m \ddot{y}$ Neglect the height of the gun, and assume $x=y=0$ at $t=0$. Then $$ \begin{aligned} & \ddot{x}=0 \\ & \dot{x}=v_0 \cos \theta \\ & x=v_0 t \cos \theta \\ & y=-\frac{-g t^2}{2}+v_0 t ...
We treat projectile motion in two dimensions, first without considering air resistance. Let the muzzle velocity of the projectile be $v_0$ and the angle of elevation be $\theta$. The Germans used a long-range gun named Big Bertha in World War I to bombard Paris. Its muzzle velocity was $1,450 \mathrm{~m} / \mathrm{s}$....
72
202
2.6
$\mathrm{km}$
class
$$ \begin{aligned} \frac{m}{k} & =\frac{m}{G m M_{\text {Sun }}}=\frac{1}{G M_{\text {Sun }}} \\ & =\frac{1}{\left(6.67 \times 10^{-11} \mathrm{~m}^3 / \mathrm{s}^2 \cdot \mathrm{kg}\right)\left(1.99 \times 10^{30} \mathrm{~kg}\right)} \\ & =7.53 \times 10^{-21} \mathrm{~s}^2 / \mathrm{m}^3 \end{aligned} $$ Bec...
Calculate the time needed for a spacecraft to make a Hohmann transfer from Earth to Mars
2.24
2.24
8.5
$10^7 \mathrm{~s}$
class
We continue to use our simple model of the ocean surrounding Earth. Newton proposed a solution to this calculation by imagining that two wells be dug, one along the direction of high tide (our $x$-axis) and one along the direction of low tide (our $y$-axis). If the tidal height change we want to determine is $h$, then...
Calculate the maximum height change in the ocean tides caused by the Moon.
0.54
0.54
5.5
$\mathrm{m}$
class
Because we are considering the possibility of the particle leaving the hemisphere, we choose the generalized coordinates to be $r$ and $\theta$. The constraint equation is $$ f(r, \theta)=r-a=0 $$ The Lagrangian is determined from the kinetic and potential energies: $$ \begin{aligned} T & =\frac{m}{2}\left(\dot...
A particle of mass $m$ starts at rest on top of a smooth fixed hemisphere of radius $a$. Determine the angle at which the particle leaves the hemisphere.
$\cos ^{-1}\left(\frac{2}{3}\right)$
48.189685
7.10
$^\circ$
class
From the thrust, we can determine the fuel burn rate:$$\frac{d m}{d t}=\frac{\text { thrust }}{-u}=\frac{37 \times 10^6 \mathrm{~N}}{-2600 \mathrm{~m} / \mathrm{s}}=-1.42 \times 10^4 \mathrm{~kg} / \mathrm{s} $$The final rocket mass is $\left(2.8 \times 10^6 \mathrm{~kg}-2.1 \times 10^6 \mathrm{~kg}\right)$ or $0.7 \...
Consider the first stage of a Saturn $V$ rocket used for the Apollo moon program. The initial mass is $2.8 \times 10^6 \mathrm{~kg}$, and the mass of the first-stage fuel is $2.1 \times 10^6$ kg. Assume a mean thrust of $37 \times 10^6 \mathrm{~N}$. The exhaust velocity is $2600 \mathrm{~m} / \mathrm{s}$. Calculate the...
2.16
2.16
9.12
$10^3 \mathrm{~m} / \mathrm{s}$
class
Find the effective annual yield of a bank account that pays interest at a rate of 7%, compounded daily; that is, divide the difference between the final and initial balances by the initial balance.
7.25
7.25
page 130-7
%
diff
Consider a tank used in certain hydrodynamic experiments. After one experiment the tank contains $200 \mathrm{~L}$ of a dye solution with a concentration of $1 \mathrm{~g} / \mathrm{L}$. To prepare for the next experiment, the tank is to be rinsed with fresh water flowing in at a rate of $2 \mathrm{~L} / \mathrm{min}$,...
460.5
460.5
Page 59-1
min
diff
A certain vibrating system satisfies the equation $u^{\prime \prime}+\gamma u^{\prime}+u=0$. Find the value of the damping coefficient $\gamma$ for which the quasi period of the damped motion is $50 \%$ greater than the period of the corresponding undamped motion.
1.4907
1.4907
page203-13
diff
Find the value of $y_0$ for which the solution of the initial value problem $$ y^{\prime}-y=1+3 \sin t, \quad y(0)=y_0 $$ remains finite as $t \rightarrow \infty$
-2.5
-2.5
Page 40-30
diff
A certain spring-mass system satisfies the initial value problem $$ u^{\prime \prime}+\frac{1}{4} u^{\prime}+u=k g(t), \quad u(0)=0, \quad u^{\prime}(0)=0 $$ where $g(t)=u_{3 / 2}(t)-u_{5 / 2}(t)$ and $k>0$ is a parameter. Suppose $k=2$. Find the time $\tau$ after which $|u(t)|<0.1$ for all $t>\tau$.
25.6773
25.6773
page336-16
diff
Suppose that a sum $S_0$ is invested at an annual rate of return $r$ compounded continuously. Determine $T$ if $r=7 \%$.
9.90
9.90
page 60-7
year
diff
A mass weighing $2 \mathrm{lb}$ stretches a spring 6 in. If the mass is pulled down an additional 3 in. and then released, and if there is no damping, by determining the position $u$ of the mass at any time $t$, find the frequency of the motion
$\pi/4$
0.7854
page202-5
s
diff
If $\mathbf{x}=\left(\begin{array}{c}2 \\ 3 i \\ 1-i\end{array}\right)$ and $\mathbf{y}=\left(\begin{array}{c}-1+i \\ 2 \\ 3-i\end{array}\right)$, find $(\mathbf{y}, \mathbf{y})$.
16
16
page372-8
diff
Consider the initial value problem $$ 4 y^{\prime \prime}+12 y^{\prime}+9 y=0, \quad y(0)=1, \quad y^{\prime}(0)=-4 . $$ Determine where the solution has the value zero.
0.4
0.4
page172-15
diff
A certain college graduate borrows $8000 to buy a car. The lender charges interest at an annual rate of 10%. What monthly payment rate is required to pay off the loan in 3 years?
258.14
258.14
page131-9
$
diff
Consider the initial value problem $$ y^{\prime \prime}+\gamma y^{\prime}+y=k \delta(t-1), \quad y(0)=0, \quad y^{\prime}(0)=0 $$ where $k$ is the magnitude of an impulse at $t=1$ and $\gamma$ is the damping coefficient (or resistance). Let $\gamma=\frac{1}{2}$. Find the value of $k$ for which the response has a p...
2.8108
2.8108
page344-15
diff
If a series circuit has a capacitor of $C=0.8 \times 10^{-6} \mathrm{~F}$ and an inductor of $L=0.2 \mathrm{H}$, find the resistance $R$ so that the circuit is critically damped.
1000
1000
page203-18
$\Omega$
diff
If $y_1$ and $y_2$ are a fundamental set of solutions of $t y^{\prime \prime}+2 y^{\prime}+t e^t y=0$ and if $W\left(y_1, y_2\right)(1)=2$, find the value of $W\left(y_1, y_2\right)(5)$.
2/25
0.08
page156-34
diff
Consider the initial value problem $$ 5 u^{\prime \prime}+2 u^{\prime}+7 u=0, \quad u(0)=2, \quad u^{\prime}(0)=1 $$ Find the smallest $T$ such that $|u(t)| \leq 0.1$ for all $t>T$.
14.5115
14.5115
page163-24
diff
Consider the initial value problem $$ y^{\prime}=t y(4-y) / 3, \quad y(0)=y_0 $$ Suppose that $y_0=0.5$. Find the time $T$ at which the solution first reaches the value 3.98.
3.29527
3.29527
Page 49 27
diff
Consider the initial value problem $$ 2 y^{\prime \prime}+3 y^{\prime}-2 y=0, \quad y(0)=1, \quad y^{\prime}(0)=-\beta, $$ where $\beta>0$. Find the smallest value of $\beta$ for which the solution has no minimum point.
2
2
page144-25
diff
Consider the initial value problem $$ y^{\prime}=t y(4-y) /(1+t), \quad y(0)=y_0>0 . $$ If $y_0=2$, find the time $T$ at which the solution first reaches the value 3.99.
2.84367
2.84367
Page 49 28
diff