NSAA NSAA Physics - Mechanics 3

Question 1

What is the impulse on a 2 kg object that changes velocity from 3 m/s to 9 m/s?

Accepted Answer

12 N·s

Answer

6 N·s

Answer

18 N·s

Answer

24 N·s

Question 2

A 10 kg box is pushed along a horizontal surface by a 40 N force. If friction is 15 N, what is the acceleration?

Accepted Answer

2.5 m/s²

Answer

1.5 m/s²

Answer

4.0 m/s²

Answer

5.5 m/s²

Question 3

Two forces of 6 N and 8 N act at right angles on an object. What is the resultant force?

Accepted Answer

10 N

Answer

2 N

Answer

7 N

Answer

14 N

Question 4

A machine does 600 J of work in 30 seconds. What is its power output?

Accepted Answer

20 W

Answer

10 W

Answer

30 W

Answer

600 W

Question 5

If the velocity of an object doubles, by what factor does its kinetic energy increase?

Accepted Answer

4

Answer

2

Answer

3

Answer

8

Question 6

A 3 kg object falls freely for 4 seconds from rest. What is its kinetic energy at that point (g = 10 m/s²)?

Accepted Answer

1200 J

Answer

120 J

Answer

240 J

Answer

2400 J