Momentum and Energy

A spring with a spring constant of 68 newtons per

meter hangs from a ceiling. When a 12-newton

downward force is applied to the free end of the

spring, the spring stretches a total distance of

• 0.18 m

• 0.59 m

• 5.7 m

• 820 m

Tags

NGSS.HS-PS2-1

As a student walks downhill at constant speed,

his gravitational potential energy

• increases and his kinetic energy increases

• increases and his kinetic energy remains the

  same

• decreases and his kinetic energy increases

• decreases and his kinetic energy remains the

  same

When 150 joules of work is done on a system by

an external force of 15 newtons in 20. seconds,

the total energy of that system increases by

• 1.5 × 10² J

• ^

  2.0 × 10² J

• 3.0 × 10² J

• 2.3 × 10³ J

Tags

NGSS.HS-PS3-1

A person on a ledge throws a ball vertically

downward, striking the ground below the ledge

with 200 joules of kinetic energy. The person

then throws an identical ball vertically upward at

the same initial speed from the same point.

What is the kinetic energy of the second ball

when it hits the ground? [Neglect friction.]

• 200 J

• 400 J

• less than 200 J

• more than 400 J

Tags

NGSS.HS-PS3-1

Two construction cranes are used to lift identical

1200-kilogram loads of bricks the same vertical

distance. The first crane lifts the bricks in

20. seconds and the second crane lifts the bricks

in 40. seconds. Compared to the power

developed by the first crane, the power

developed by the second crane is

• the same

• twice as great

• half as great

• four times as great

A 1.47-newton baseball is dropped from a height of 10.0 meters and falls through the air to the ground. The kinetic energy of the ball is 12.0 joules the instant before the ball strikes the ground. The maximum amount of mechanical energy converted to internal energy during the fall is

• 2.7 J

• 12.0 J

• 14.7 J

• 26.7 J

The amount of electric energy consumed by a 60.0-watt lightbulb for 1.00 minute could lift a 10.0 newton object to a maximum vertical height of

• 6.00 m

• 36.7 m

• 360. m

• 600. m

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

A golf club hits a stationary 0.050-kilogram golf ball with an average force of  $5.0\times10^3$  Newtons, accelerating the ball to a speed of 44 meters per second. What is the magnitude of the impulse imparted to the ball by the golf club?

•  $2.2\ N\cdot s$  

•  $1.1\times10^4\ N\cdot s$  

•  $880\ N\cdot s$  

•  $2.2\ \times10^5\ N\cdot s$  

Tags

NGSS.HS-PS2-1

A tennis player’s racket applies an average force of 200. newtons to a tennis ball for 0.025 second. The average force exerted on the racket by the tennis ball is

• 0.025 N

• 200. N

• 5.0 N

• 80.0 N

Tags

NGSS.HS-PS2-1

NGSS.HS-PS2-3

A spring has an unstretched length of 0.40 meter. The spring is stretched to a length of 0.60 meter when a 10.-newton weight is hung motionless from one end. The spring constant of this spring is

• 10. N/m

• 25 N/m

• 17 N/m

• 50. N/m