Work Energy and Power

The coefficient of kinetic friction between a large box and the floor is 0.21. A person pushes horizontally on the box with a force of 165 N for a distance of 2.8 m. If the mass of the box is 72 kg, what is the total work done on the box? (Round your answer to a whole number)

• 51

• 49

• 47

• 45

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-1

Work is zero if the force has a component in the direction opposite of motion.

• True

• False

A 3 kg plate is tossed across the room with an acceleration of 13 m/s² in 2.5 sec. Calculate the amount of power it took to toss the plate.

• 290.5 W

• 1267.5 W

• 507 W

• 3000 W

Tags

NGSS.HS-PS2-1

An object weighing 20 N moves horizontally toward the right a distance of 5.0 m. What is the work done on the object by the force of gravity?

• The work done on the object by the force of gravity is 50 J.

• The work done on the object by the force of gravity is zero joules.

• The work done on the object by the force of gravity is 4.0 J.

• The work done on the object by the force of gravity is 0.25 J.

• The work done on the object by the force of gravity is 100 J.

Tags

NGSS.HS-PS3-1

You pick up a 3.8 kg can of paint from the ground and lift it to a height of 1.4 m. You hold the can stationary for half a minute, waiting for a friend on a ladder to take it. How much work do you do during this time (when the can of paint was stationary)?

• 52 J

• 30 J

• 0 J

• 25 J

You raise a bucket of water from the bottom of a well that is 12 m deep. The mass of the bucket and the water is 5.00 kg, and it takes 15 s to raise the bucket to the top of the well. How much power is required?

• 39 W

• 41 W

• 43 W

• 45 W

Tags

NGSS.HS-PS3-1

Calculate the KE of a runner that has a mass of 80 kg and is running at a velocity of 8 m/s

• 5120 J
• 320 J
• 640 J
• 2560 J

Tags

NGSS.HS-PS3-1

Energy due to motion is ____________ energy. 

• Potential 
• Energy
• Kinetic
• Friction

Tags

NGSS.HS-PS3-2

__________ is stored energy. 

• Potential
• Kinetic
• None of the above 
• All of the above 

Tags

NGSS.HS-PS3-2

Gravitational potential energy depends on the ________ and ________ of the object. 

• Height and mass
• Friction and movement
• Mass and Movement
• Height and Friction 

Tags

NGSS.MS-PS2-4

NGSS.MS-PS3-2