PHYSICS 114 FINAL UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

PHYSICS 114 FINAL UPDATED ACTUAL QUESTIONS AND
CORRECT ANSWERS

Question:
1. Two objects of the same mass fall from different heights. If air friction is negligible then they will reach
the ground.
Answer:
At different speeds, times but the same acceleration.

Question:
2. A projectile of mass m1 is launches horizontally from a height of 100m and speed of 10 m/s. Anther
projectile of mass m2 free falls from the same height. The experiment is taking place on Mars, where the
gravity is about 1/2 of that on Earth. Atmospheric resistance can be neglected. The two projectiles will
land on the ground:
Answer:
at the same time.

Question:
3. A projectile has a velocity of 3t(i)-t^2(j), where t is the time in seconds while (i) and (j) are the unit
vectors for x and y-axis. At t=2 seconds, its total acceleration magnitude will be:
Answer:
5 m/s^2

Question:
4. An object is left to slide without friction from the top of an inclined plane of angle (z). The object
accelerating with:
Answer:
g sin(z)

Question:
5. A mass of 1 kg is at rest on a horizontal surface with friction coefficient u. When a horizontal force of
5N is applied to the object then it barely moves. If g = 9.8 m/s^2 then u is about:
Answer:
0.5

Question:
6. One claims that two springs connected in parallel to each other will exhibit a greater constant than if the
same two springs were connected in a series. This statement is likely:
Answer:
Correct.

Question:
7. An object of mass m is attached to a spring that is on an inclined plane of angle theta. The object is at a
rest. If the spring is elongated by x then one can argue to the spring's constant k will be equal to:
Answer:

, Question:
8. A student calculates the friction coefficient between an object and a horizontal surface. The student
argues that this coefficient should be the same if the experiment takes place between the same object the
same surface but inclined. The student's argument is:
Answer:
Correct.

Question:
9. If you apply Newton's law on two objects of different masses that are free falling from different heights
with no air resistance then you will conclude the both object objects accelerate:
Answer:
9.8

Question:
10. The total acceleration of a swinging pendulum can have a linear and a centripetal (aka radial)
component. Subsequently, someone argues that the TOTAL ACCEL- ERATION of the pendulum can
NEVER be ZERO, in that, when one component is zero the other is not. This statement is :
Answer:
Correct.

Question:
11. A stone is attached to a string and you twirl it above your head along the horizontal at a constant
angular speed. The CENTRIPETAL. (aka radial) ACCELERATION at ANY point of the stone's circular
trajectory depends on:
Answer:
The length of the string.

Question:
12. The sum of the forces acting on an object along the x-axis is zero. The sum of the forces acting on the
same object along the y-axis is not zero. Then we can safely assume that the acceleration of the object:
Answer:
Will be non-zero along the y-axis.

Question:
13. A pseudo-force is a force:
Answer:
That exists only when the system of reference is also accelerating.

Question:
14. One argues the pendulum bob we experimented with has MAXIMUM linear speed where its LINEAR
acceleration is zero. This statement is:
Answer:
Correct.

Question:
15. A person steps on a scale inside an elevator moving from the 1st to the 2nd floor at a constant speed 2.0
m/s^-1. The scale shows: