Energy, Work and Power

Bob (80 kg) uses 180 N of force to get him up the slope. The vertical distance is 2 m and the diagonal is 10 m. Calculate the work he does.

• 1600 J

• 160 J

• 3600 J

• 1800 J

Tags

NGSS.MS-PS2-2

A weight-lifter raises a 2000N weight through a vertical height of 2.0m in 0.80s. What useful power does he develop in doing this?

• 800 W

• 700W

• 4000W

• 5000W

Tags

NGSS.MS-PS3-4

Which of these items is not part of the law of conservation of energy?

• energy cannot be created

• energy cannot be destroyed

• energy can be transferred between forms

• energy is destroyed by friction

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-4

At which point(s) on the roller coaster is the kinetic energy at its maximum?

• A

• B

• C

• D

Tags

NGSS.MS-PS3-1

At which point(s) on the roller coaster is the gravitational potential energy at its maximum?

• A

• B

• C

• D

Tags

NGSS.MS-PS3-2

Groot rescues Rocket from the bottom of a deep pit. Groot expends 1000 J of energy lifting Rocket who has a mass of 50 kg out of the pit. How deep is the pit?

• 0.5 m

• 2 m

• 4 m

• 10 m

Tags

NGSS.MS-PS2-4

How do you calculate power?

• P = W/t

• P = E/t

• P = w * t

• P = bbq/chicken

Gravitational potential energy depends on the ________ and ________ of the object. 

• Height and mass

• Friction and movement

• Mass and Movement

• Height and Friction 

Tags

NGSS.MS-PS3-2

Why does the total amount of mechanical energy stay constant in a system?

• energy is not created or destroyed

• energy leaves

• energy enters

• energy is not converted from one form into another

Tags

NGSS.MS-PS3-5

What is the formula for calculating the total amount of mechanical energy?

• ME = KE + PE

• KE = ME + PE

• PE = KE + ME

• ME = 1/2 mv²

Tags

NGSS.MS-PS3-4