Physics Work Energy Power

Bob (80 kg) uses 180 N of force to get him up the slope. The vertical distance is 2 m and the diagonal is 10 m. Calculate the work he does.

• 1600 J

• 160 J

• 3600 J

• 1800 J

Tags

NGSS.HS-PS2-1

If the net work done on an object is negative, then the object’s kinetic energy...

• decreases

• remains the same

• increases

• is zero

Tags

NGSS.HS-PS3-1

On a force versus change in position graph, the area under the curve is a representation of...

• power

• KE

• PE

• work

How far does a car that pulled with a 5,000 N force go if 18,000 J of work is done on it?

• 3.8 m

• 3.7 m

• 3.2 m

• 3.6 m

Groot rescues Rocket from the bottom of a deep pit. Groot expends 1000 J of energy lifting Rocket who has a mass of 50 kg out of the pit. How deep is the pit?

• 0.5 m

• 2 m

• 4 m

• 10 m

Tags

NGSS.HS-PS2-1

Which of the following would be a measure of Work?

• 13 W

• 14 m

• 45 J

• 10 N

Tags

NGSS.MS-PS3-5

Bowling Ball A is dropped from a point halfway up a cliff. A second identical bowling ball, B, is dropped

simultaneously from the top of the cliff. Comparing the bowling balls at the instant they reach the ground,

which of the following are correct? Neglect air resistance.

• Ball A has half the kinetic energy and takes half the time to hit the ground as Ball B.

• Ball A has half the kinetic energy and takes one-fourth the time to hit the ground as Ball B.

• Ball A has half the final velocity and takes half the time to hit the ground as Ball B.

• Ball A has one-fourth the final velocity and takes one-fourth the time to hit the ground as Ball B.

• None of these are correct.

Tags

NGSS.HS-PS2-1

A net force (Fcosθ) acts on an object moving in the

positive x-direction along the axis over a distance of 4

meters, depicted in the graph at right. Find the work done by the force in the interval from 0.0 to 2.0 m.

• 0 J

• 3 J

• 3/cosθ J

• 6 J

A child pushes horizontally on a box of mass m which moves with constant speed v across a horizontal floor.

The coefficient of friction between the box and the floor is μ. At what rate does the child do work on the box?

• μmgv

• mgv

• μmg/v

• mgv/μ

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-2

If L, M, and T denote the dimensions of length, mass, and time, respectively, what are the dimensions of power?

• L²M/T²

• M²L/T²

• M²L/T³

• ML²/T³