Work & Power

In which case is work being done?

• A

• B

• C

• D

Tags

NGSS.HS-PS2-1

What is the work done on a 0.90 kg model airplane moves at a constant speed of 19 m/s on a circle that is 1 m off the ground?

• 8.82 J

• 162 J

• 8.82 J

• 0 J

Tags

NGSS.HS-PS3-1

Joel and Jerry push against a car that has stalled, trying unsuccessfully to get it moving. Jerry stops after 10 min, while Joel is able to push for 5.0 min longer. Compare the work they do on the car.

• Joel does 75% more work than Jerry.

• Joel does 50% more work than Jerry.

• Jerry does 50% more work than Joel.

• Joel does 25% more work than Jerry.

• Neither of them does any work.

Tags

NGSS.HS-PS2-1

ln the Empire State Building Run-Up, competitors race up the 1576 steps (86 flights) of the Empire State Building, climbing a total vertical distance of 320 m. How much work does a m 74 kg racer do?

• 2.321 × 10⁵ Joules

• 2.326 × 10⁵ Joules

• 2.318 × 10⁵ Joules

• 2.317 × 10⁵ Joules

Tags

NGSS.HS-PS3-1

If a 74 kg racer took 798 s to climb the 320 m, how power did she developed?

• 291 Watts

• 281 Watts

• 317 Watts

• 313 Watts

Tags

NGSS.HS-PS3-1

This weight lifter raised 105 kg to a height of approximately 2.31 m in 9 seconds. How much power did he developed?

• 264 Watts

• 1029 Watts

• 2,377 Watts

• 4,009 Watts

Tags

NGSS.HS-PS3-1

Three cars (car F, car G, and car H) are moving with the same speed and slam on their brakes. The most massive car is car F, and the least massive is car H. If the tires of all three cars have identical coefficients of kinetic friction with the road surface, which car travels the longest distance to skid to a stop?

• They all travel the same distance in stopping.

• Car F

• Car G

• Car H

Tags

NGSS.HS-PS2-1

A construction worker uses a pulley and a rope to raise an 85 kg person to a height of 2 m in 6 s. How much did he do?

• 1,670 J

• 833 J

• 278 J

• 417 J

Tags

NGSS.HS-PS2-1

NGSS.HS-PS3-1

A construction worker uses a pulley and a rope to raise an 85 kg person to a height of 2 m in 6 s. How much power is he supplying?

• 1,670 W

• 833 W

• 278 W

• 417 W

Tags

NGSS.HS-PS3-1

Two people are lifting the same weight as shown in the animation. If they both do 10 reps, who will do the most work?

• Bro A

• Bro B

• They both will do the same work

• Can't tell without knowing the weight they are lifting