lab 5 Work Energy Theorem

Question 1

If there are no other external forces acting on the system and doing work, the sum of these two forms of energy is

Answer 1

conserved.

Question 2

If an amount of work, W, is done on a system, then the kinetic energy, KE, of the system

Answer 2

changes. The change in the kinetic energy is equal to the amount of work done. Stated quantitatively:

W= ∆KE= 1/2 〖mv〗_f^2 - 1/2 〖mv〗_i^2

Question 3

The Work-Energy Theorem presents a way of dealing with kinematic quantities in mechanics without regard for

Answer 3

vector direction

Question 4

These directionless quantities, such as kinetic energy, are called

Answer 4

scalars

Question 5

In the simulation on Work-Energy Theorem, if the area under the curve is not equal to the change in kinetic energy, then that means some energy was lost to the environment through friction.

Answer 5

True

Question 6

What is the kinetic energy of an object that has a total mechanical energy of 200 J if it has a potential energy is 65 J?

Answer 6

135 J

Question 7

In the given figure, a ball of mass m = 5.00 kg is dropped from point A and it falls to the ground with no air resistance. Which of the following is TRUE?

Answer 7

The potential energy of the ball decreases as it moves from point A to B then from B to C.

Question 8

In the pendulum simulation, if friction is in fact present and not ignored, then as the pendulum swings back and forth?

Answer 8

Total mechanical energy decreases.

Question 9

When an object slows down, then the total work done on the object is negative

Answer 9

True

Question 10

A 3.15-kg particle has a speed of 2.0 m/s at point A and a kinetic energy of 7.5 J at point B.
What is the total work done on the particle as it moves from A to B?

Answer 10

1.2 J

Question 11

Refer to the given figure of a swinging pendulum, at which point is its gravitational potential energy maximum?

Answer 11

Point 1

Question 12

Let the pendulum in the figure be the pendulum you used in the simulation. At which point is its kinetic energy maximum?

Answer 12

Point 3

Question 13

The figure is the graph of Spring Force versus Displacement. For an oscillating spring. Based on the graph, which of the following statements is NOT a valid conclusion about the motion?

Answer 13

There is friction acting on the spring

Question 14

In the given figure, what will be the speed of the ball just before it strikes the ground if the height of the cliff is 20 m?

Answer 14

20m/s