Question 1

A uniform pressure of 21 × 105 N/m2 is applied to all six sides of a copper cube.What is the percentage change in volume of the cube? (for copper,B = 14 × 1010 N/m2)

Accepted Answer

A)  2.4 × 10−2 % 
B)  1.5 × 10−3 % 
C)  8.4 × 10−2 % 
D)  0.5 × 10−3 %

Question 2

If it takes 8.0 N to stretch a spring 6.0 cm,and if the spring is then cut in half,what force does it take to stretch one of the halves 3.0 cm?

Accepted Answer

A)  2.0 N 
B)  4.0 N 
C)  8.0 N 
D)  16 N

Question 3

When an object is moving in simple harmonic motion,which of the following is at a minimum when the displacement from equilibrium is zero?

Accepted Answer

A)  the magnitude of the velocity 
B)  the magnitude of the acceleration 
C)  the kinetic energy 
D)  the total mechanical energy

Question 4

Doubling the displacement from equilibrium of an object in simple harmonic motion will bring about a change in the magnitude of the object's acceleration by what factor?

Accepted Answer

A)  4.0 
B)  2.0 
C)  1.0 
D)  0.5

Question 5

A runaway railroad car,with mass 30 × 104 kg,coasts across a level track at 2.0 m/s when it collides with a spring-loaded bumper at the end of the track.If the spring constant of the bumper is 4.0 × 106 N/m,what is the maximum compression of the spring during the collision? (Assume the collision is elastic. )

Accepted Answer

A)  0.77 m 
B)  0.55 m 
C)  0.34 m 
D)  1.07 m

Question 6

Suppose a 0.30-kg mass on a spring-loaded gun that has been compressed 0.20 m has elastic potential energy of 1.0 J.How high above the spring's equilibrium point can the gun fire the mass if the gun is fired straight up?

Accepted Answer

A)  0.10 m 
B)  0.34 m 
C)  0.24 m 
D)  0.14 m

Question 7

A simple pendulum of length 2.00 m has a mass of 100 g attached.It is drawn back 30.0° and then released.What is the maximum speed of the mass?

Accepted Answer

A)  1.14 m/s 
B)  4.58 m/s 
C)  2.29 m/s 
D)  1.62 m/s

Question 8

The position of a 0.64-kg mass undergoing simple harmonic motion is given by x = (0.160 m)cos (πt/8).What is its period of oscillation?

Accepted Answer

A)  100 s 
B)  32 s 
C)  16 s 
D)  8.0 s

Question 9

An object is attached to a spring,and its frequency of oscillation is measured.Then another object is connected to the first object,and the resulting mass is nine times the original value.By what factor is the frequency of oscillation changed?

Accepted Answer

A)  9 
B)  3 
C)  1/3 
D)  1/9

Question 10

Three identical springs,each with spring constant k,are attached in parallel to a mass,which is then set into simple harmonic motion.What would be the spring constant of a single spring which would result in the same frequency of oscillation as the parallel springs?

Accepted Answer

A)  k 
B)  k/3 
C)  3k 
D)

Question 11

An object moving in simple harmonic motion has an amplitude of 0.020 m and a maximum acceleration of 20 m/s2.What is the frequency of the system?

Accepted Answer

A)  0.40 Hz 
B)  5.0 Hz 
C)  10.1 Hz 
D)  32 Hz

Question 12

I attach a 2.0-kg block to a spring that obeys Hooke's Law and supply 4.0 J of energy to stretch the spring.I release the block;it oscillates with period 0.30 s.The amplitude is:

Accepted Answer

A)  38 cm. 
B)  19 cm. 
C)  9.5 cm. 
D)  4.3 cm.

Question 13

A mass of 0.40 kg,hanging from a spring with a spring constant of 160 N/m,is set into an up-and-down simple harmonic motion.What is the speed of the mass when moving through a point at 0.05 m displacement? The starting displacement of the mass is 0.10 m from its equilibrium position.

Accepted Answer

A)  zero 
B)  1.4 m/s 
C)  1.7 m/s 
D)  1.2 m/s

Question 14

The motion of a piston in an automobile engine is nearly simple harmonic.If the 1-kg piston travels back and forth over a distance of 12.0 cm,what is its maximum speed when the engine is running at 3000 rpm?

Accepted Answer

A)  4.71 m/s 
B)  9.42 m/s 
C)  44.0m/s 
D)  22.0 m/s

Question 15

Four identical springs each have the same spring constant k.If these four springs are attached end to end forming a spring four times the length of one of the original springs,what will be the spring constant of the combination?

Accepted Answer

A)  k 
B)  k/4 
C)  4k 
D)  1.41k

Question 16

A mass on a spring vibrates in simple harmonic motion at a frequency of 4.0 Hz and amplitude of 8.0 cm.If the mass of the object is 0.25 kg,what is the spring constant?

Accepted Answer

A)  40 N/m 
B)  87 N/m 
C)  126 N/m 
D)  158 N/m

Question 17

A 0.40-kg object,attached to a spring with spring constant k = 10 N/m,is moving on a horizontal,frictionless surface in simple harmonic motion of amplitude of 0.080 m.What is its speed at the instant when its displacement is 0.040 m? (Hint: Use conservation of energy. )

Accepted Answer

A)  17 m/s 
B)  35 cm/s 
C)  3.5 cm/s 
D)  6.9 cm/s

Question 18

A 0.20-kg mass is oscillating on a spring over a horizontal,frictionless surface.When it is at a displacement of 2.6 cm from equilibrium,it has a kinetic energy of 2.7 J and a spring potential energy of 2.2 J.What is the maximum speed of the mass during its oscillation?

Accepted Answer

A)  3.7 m/s 
B)  4.7 m/s 
C)  6.0 m/s 
D)  7.0 m/s

Question 19

The oxygen molecule (O2)may be regarded as two masses connected by a spring.In vibrational motion,each oxygen atom alternately approaches,then moves away from the center of mass of the system.If each oxygen atom of mass m = 2.67 × 10−26 kg has a vibrational energy of 6.4 × 10−21 J and the effective spring constant is 50 N/m,then what is the amplitude of oscillation of each oxygen atom?

Accepted Answer

A)  3.2 × 10−11 m 
B)  1.6 × 10−11 m 
C)  1.1 × 10−11 m 
D)  8.0 × 10−12 m

Question 20

A 0.20-kg block rests on a frictionless,level surface and is attached to a horizontally aligned spring with a spring constant of 80 N/m.The block is initially displaced 4.0 cm from the equilibrium point and then released to set up a simple harmonic motion.What is the speed of the block when it passes through the equilibrium point?

Accepted Answer

A)  2.1 m/s 
B)  1.6 m/s 
C)  0.80 m/s 
D)  0.57 m/s

Exam 11: Energy in Thermal Processes Heat and Internal Energy: Part A

A uniform pressure of 21 × 10⁵ N/m² is applied to all six sides of a copper cube.What is the percentage change in volume of the cube? (for copper,B = 14 × 10¹⁰ N/m²)