Work, Power and Simple Machines

Frank does 2400 J of work in climbing a set of stairs. If he does the work in 6 seconds, what is his power output?

• 14400 Watts

• 400 Watts

• 40 Watts

• 0.0025 Watts

A student who weighs 500 Newton's climbed the stairs from the first floor to the third floor, 15 meters above, in 20 seconds. What was her power output?

• 375 Watts

• 25 Watts

• 300 Watts

• 33 Watts

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

If 55 Watts of power are used to do 275 J of work, how many seconds will it take for the work to be completed?

• 1 second

• 5 seconds

• 0.2 seconds

• 30 seconds

comparison of a machine's work output with work input

• watt
• machine
• work
• mechanical efficiency

unit used to express power

• watt
• machine
• work
• mechanical efficiency

Which type of simple machine would help you raise a flag on a flagpole?

• pulley
• lever
• wedge
• wheel and axle

Tags

NGSS.MS-PS2-1

Which type of simple machine is a playground slide?

• inclined plane
• screw
• wheel and axle
• wedge

Tags

NGSS.3-5-ETS1-1

The steering wheel of a car is what type of simple machine?

• wheel and axle
• lever 
• pulley
• wedge

Stairs

• wedge

• pulley

• inclined plane

• wheel and axle

Tags

NGSS.MS-PS2-2

An inclined plane has an IMA of 2.5 and a height of 3 m. How long is the inclined plane?

• 5.5 m

• 1.2 m

• 7.5 m

• 0.5 m