Physics Power

In which of the following situations do your arms do work on books?

• holding a heavy stack of books while standing

• carrying a heavy stack of books

• dropping a stack of books onto a table

• picking up a pile of books from the floor

Tags

NGSS.MS-PS3-5

What unit do we use for measuring power?

• Watts 

• Joules 

• Newtons 

• ft/lbs

What is the difference between calculating power and work?

• Power takes into account the time it takes to complete a task

• Work takes into account the time it takes to complete a task

• Power is force/area

• Work is force/area

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

Mr. B's and Mr. P's classes competed in a game of tug of war. Mr. B's class pulled to the right with a force of 4,000 N. Mr. P's class pulled to the left with a force of 5,000 N. As a result the rope moved 5.1 m to the left. How much work was done by the net force?

• 4100 J

• 3100 J

• 5100 J

• 45900 J

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-4

A 5000N block is lifted 10 m. Calculate the work done.

• 50000 J

• 5000 J

• 500 J

• 50 J

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

A 16 N force is applied to an object and 96 J of work is done. How far was the object moved?

• 6 m

• 16 m 

• 80 m 

• 1536 m 

How much force is used when 350 J is produced to move a car 5 m?

• 70 N

• 17500 N

• 355 N

• 175 N

A 10 kg mass is lifted to 3 m. What is its weight? What is its potential energy? How much work is being done?

• Weight = 30 N

  PE = 30 J

  Work = 294 J

• Weight = 10 kg

  PE = 10 J

  Work = 30 J

• Weight = 98 N

  PE = 294 J

  Work = 294 J

• Weight = 98 N

  PE = 294 J

  Work = 30 J

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-4

If you pull the trolley along a flat floor horizontally. Which force do you use to calculate the work done.

• Weight

• Pulling force

Mike and Ian move 50 m on a snow lift which uses 750 N of force to move them in 75 seconds. Calculate the power of the lift.

• 750 W

• 500 W

• 7500 W

• 2812500 W

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2