Science Bowl Practice Questions

Physics - 3

16.

Short Answer: A box is initially at rest on a horizontal, frictionless table. If a force of 10 Newtons acts
on the box for 3 seconds, what is the momentum of the box at the end of the 3 second interval?

ANSWER: 30 NEWTON-SECONDS or 30 KILOGRAM-METER PER SECOND

17.

Multiple Choice: A block of metal which weighs 60 newtons in air and 40 newtons under water has a
density, in kilograms per meter cubed, of:

w) 1000
x) 3000
y) 5000
z) 7000

ANSWER: X -- 3000

18.

Short Answer: A 10 kilogram body initially moving with a velocity of 10 meters per second makes a
head-on collision with a 15 kilogram body initially at rest. The two objects stick together. What is the
velocity of the combined system just after the collision?

ANSWER: 4 METERS PER SECOND

19.

Short Answer: A certain spring is known to obey Hooke's Law. If a force of 10 newtons stretches the
spring 2 meters, how far will a 30 newton force stretch the spring?

ANSWER: 6 METERS