What is the equation for work?

• E_p= mgh

• W = F x d

• F = mg

• F = ma

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

• Weight

• Pulling force

Tags

NGSS.HS-PS2-1

If you pull the trolley vertically upwards using a crane. Which force do you use to calculate the work done.

• Weight

• Pulling force

The force used in the work equation has to always be acting in the same direction as the movement of the object.

• True

• False

Tags

NGSS.HS-PS2-1

Which equation is the one for power?

• P = F/A

• W = F x t

• p = m v

• P = W / t

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-PS2-2

Ian and Steve ski down the 75 m slope in 80 seconds using 400 N of penguin force. Calculate their penguin power!

• 375 W

• 37.5 W

• 426.7 W

• 240 000W

Tags

NGSS.HS-PS3-1

Mike and Peter are climbing to the top. Both take the same time, do the same route, but Mike has a mass of 25 kg while Peter has a mass of 30 kg. (He is a bit taller). Which penguin does the most work and why.

• Mike as shorter people have shorter legs and does more work.

• Peter as he does more work over the same time than Mike because he has a bigger weight force

• Mike and Peter do the same amount of work as they do the same route in the same time.

• Peter as he does the same amount of work but in a smaller amount of time.

Tags

NGSS.HS-PS2-1

The roller coaster car has a mass of 500 kg. It is pulled from position 1 to 2 (30 m) by a motor. At the top of the ride the vertical distance top to bottom is 20 m. The motor pulls the car with a 4000 N force. Calculate the gravitational potential energy of the car at the top of the ride.

• 100 000J

• 120 000J

• 800 000J

• 90 000J

The roller coaster car has a mass of 500 kg. It is pulled from position 1 to 2 (30 m) by a motor. At the top of the ride the vertical distance top to bottom is 20 m. The motor pulls the car with a 4000 N force. Calculate the work done getting the car to the top of the ride.

• 100 000J

• 120 000J

• 800 000J

• 90 000J