Physics Spring Final Study Guide 1.
The gravitational potential energy that is possessed by an object is dependent on the object’s: a. acceleration b...
The gravitational potential energy that is possessed by an object is dependent on the object’s: a. acceleration b. momentum c. position d. speed e. elastic potential energy
2.
As a ball falls freely toward the ground, the sum of its kinetic and gravitational potential energy: a. decreases b. increases c. remains the same
3.
A spring with a spring constant of 4.0 N/m is compressed by a force of 1.2 N. What is the elastic potential energy stored in this compressed spring? a. 0.18 J b. 0.36 J c. 0.60 J d. 4.8 J e. 5.9J
4.
The work done in lifting a 1 kg apple one meter near the Earth’s surface is approximately: a. 0.01 J b. 1 J c. 10 J d. 100 J e. 1000 J
Physics Spring Final Review Guide
5.
A railroad car of mass m is moving with speed v when it collides with and connects to a second railroad car of mass 3m, initially at rest, as shown below. How do the speed and kinetic energy of the connected cars compare to those of the single car of mass m before the collision?
a. b. c. d. e.
6.
Speed Less Less The same The same Greater
Kinetic Energy Less The same Less The same The same
Which of the following is true of the conservation of momentum and kinetic energy? a. Momentum is conserved only in inelastic collisions b. Momentum is conserved only in elastic collisions c. Kinetic energy is conserved only in inelastic collisions d. Kinetic energy is conserved only in elastic collisions e. Both require the same conditions in order to be conserved
Physics Spring Final Review Guide
7.
A block of mass 3 kg slides along a horizontal surface that has negligible friction except for one section, as shown below. The block arrives at the rough section with a speed of 5 m/s and leaves it 0.5 s later with a speed of 3 m/s. What is the magnitude of the work done by the frictional force exerted on the block by the rough section of the surface?
a. b. c. d. e.
8.
24 J 16 J 8J 6J 3J
In problem #7 above, what is the magnitude of the frictional force exerted on the block by the rough section of the surface? a. 30 N b. 12 N c. 4.5 N d. 4 N e. 3 N
Physics Spring Final Review Guide
9.
A block released from rest at position A slides with negligible friction down an inclined track, around a vertical loop, and then along a horizontal portion of the track as shown below. The block never leaves the track. After the block is released, in which of the following sequences of positions is the speed of the block ordered from fastest to slowest?
a. b. c. d. e.
10.
B B D E E
C E C B D
D C E C C
E D B D B
Refer to the situation in problem #9 above. Which of the following is true of the net force on the block when it is at position C? a. It is directed vertically downward b. It is directed vertically upward only c. It is directed to the left only d. It is directed to the right only e. It has components both to the left and vertically downward
Physics Spring Final Review Guide
11.
A person throws a marble straight up into the air, releasing it a short height above the ground and catching it at that same height. If air resistance is negligible, which of the following graphs of position y versus time t is correct for the motion of the marble as it goes up and then comes down?
Physics Spring Final Review Guide
Sample Free Response Questions (FRQs) Sample FRQ 1: Momentum and Kinematics Model (2D)
Definition of Gravitational Potential Energy Conservation of Energy Spring potential energy Gravitational potential energy Conservation of Momentum / Definition of Kinetic Energy Conservation of Momentum & Elastic vs. Inelastic Collisions W = change in kinetic energy W=Fd, use kinematics to find d Conservation of Energy Centripetal Force Kinematics
FRQ 1 Solution a. Impulse = 12 Ns b. vhorizontal = 2.4 m/s ci. vafter = 2 m/s cii. To the right d. Change in K = Kfinal – Kinitial = 154 J e. Distance between two objects = 0.2 m (xblock = 1.2 m, xcube = 1m)
FRQ 2 Solution a. PEspring = 50 J b. vc = 4.58 m/s c. vfinal = 3.05 m/s d. d = 1.16 m
FRQ 3 Solution a. ttotal = 3.6 s bi. vAfinal = 1.2 m/s bii. To the right c. The collision is NOT elastic (Kinitial = 3125 J, Kfinal = 2484 J; loss of kinetic energy)
Physics Spring Final Review Guide
FRQ 4 Solution a.
3.5 2 v 02 1 2 Mgh = M ( 3.5v 0 ) , therefore, h = 2 g 2
b.
v = 0.5 v0
c.
μ=
d.
The collision is inelastic; there is a loss of kinetic energy ( K = 3Mv 02 )
2v 02 Dg
FRQ 5 Solution a. v2after = 0.5 m/s, to the right b. m = 3.1 kg c. a = -0.73 m/s2 d. dtotal = 5.5 m e. h = 0.12 m