Chapter 4 Work and Energy

Find the efficiency of a machine that does 650 J of work if the input work is 925 J.

• .70 %

• 70%

• 1.42 %

• 64.3 %

Check ALL the options that show an example of potential energy.

• a soccer ball laying on the ground

• a train racing down the tracks

• a pineapple

• a bird flying to its nest

• a rollercoaster at the top of a hill

Tags

NGSS.MS-PS3-2

Find the KE of a trapeze artist with a mass of 53 kg who is flying through the air with a speed of 5 m/s.

• 610.5 J

• 1325 J

• 132.5 J

• 662.5 J

Tags

NGSS.MS-PS3-1

Calculate the work done when you lift a 25 kg log 1.7 meters in the air.

• 14.71 J

• 425 J

• 42.5 J

• 14 J

Tags

NGSS.MS-PS3-2

A battery holds ________.

• kinetic energy

• gravitational potential energy

• nuclear potential energy

• chemical potential energy

Tags

NGSS.HS-PS1-4

NGSS.HS-PS3-1

Find the efficiency of a machine that does 455 J of work if the input work is 1050 J.

• 43 %

• .43 %

• 2.31 %

• 23.1 %

mechanical energy = _________ + ________

• heat energy; potential energy

• kinetic energy; unused energy

• potential energy; kinetic energy

• chemical energy; thermal energy

A block is pushed with a force of 88 N and moves a distance of 12 m across the floor. How much work is done in moving the block?

• 100 J

• 1056 J

• 7.33 J

• 452 J

Tags

NGSS.MS-PS3-5

Calculate the mechanical advantage of a hammer if the input force is 300 N and the output force is 1150 N.

• 3.83 N

• 8.70 N

• 345 N

• 345,000 N

Tags

NGSS.MS-PS2-2

Find the kinetic energy of a jogger with a mass of 42 kg moving forward at a speed of 4 m/s.

• 318 J

• 672 J

• 336 J

• 168 J

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-4