7.2 POTENTIAL AND KINETIC ENERGY

Which point has the most potential energy?

• G

• F

• B

• A

Tags

NGSS.MS-PS3-2

Potential energy depends on the ________ and ________ of the object.

• Height (position)

• Mass

• Speed

• Friction

Kinetic energy can be calculated using the formula KE = 1/2mv². What is the kinetic energy of a bicycle that has a mass of 20 kg and is traveling at a velocity of 10 m/sec?

• 10 J

• 100 J

• 1000 J

• 10,000 J

Elastic potential energy is energy stored in an object, such as a spring, due to the object being stretched or compressed. In which position is it most likely that the spring has lost its elastic potential energy?

• W

• Y

• X

• Z

Tags

NGSS.MS-PS3-2

A force 480 N of that changes the spring length by 0.25 m, calculate the elastic potential energy in Joule. (no need to put the unit in your answer).

Elastic Potential Energy=1/2 x Force x extension length

(a)  

The highest inhabited town in the world has an elevation of 5334 m above sea level. What would be the gravitational potential energy of a 64 kg person in this town?

Gravitational Potential Energy = mass x gravitational potential energy x height

• 341,376 J

• 83.3 J

• 3,413,760 J

• 34,834.3 J

An Olympic high jumper, with a mass of 82 kg, has a maximum gravitational potential energy of 1970 J. How high was the jump?

Gravitational potential energy = mass x gravitational acceleration x height

• 24 m

• 161,540 m

• 2.4 m

• 201 m

What two factors affect an object's kinetic energy?

• area and volume

• mass and weight

• weight and height

• mass and speed

Tags

NGSS.MS-PS3-1

Lilly's cat ran through your yard. The cat has a mass of 5 kg. He is running at a speed of 3 m/s. What is the kinetic energy of the cat as he runs? Kinetic energy = 1/2 x mass x velocity ^2

• 8.5 J

• 45 J

• 7.5 J

• 22.5 J

What is the mass of a ball that has a kinetic energy of 115 J and is traveling at 9 m/s?

Kinetic energy = 1/2 x mass x velocity ^2

• 1035 kg

• 23.5 kg

• 12.8 kg

• 2.84 kg