Calculating Kinetic Energy

Kinetic Energy

physical science

Multiple Choice

What is kinetic energy?

• When an object is in motion
• When an object is not in motion
• all of the above
• none of the above

Multiple Choice

What is the unit of measurement for kinetic energy?

• Watts
• Joules
• Newtons
• Meters

KE = 1/2 mv²

KE = 1/2 * 60.0 kg * 3.0²

KE = 1/2 * 60 * 9

KE = 1/2 * 540

KE = 270 Joules

** BE CAREFUL**

• velocity is the ONLY VARIABLE that is squared

• when solving, square velocity FIRST

• multiply v² by mass

• divide by 2 (or multiply by 0.5)

An object moving with a speed of 35 m/s and has a mass of 2.45 kg, what is its kinetic energy? 

KE = 1/2 mv²

KE = 1/2 * 2.45 * 35²

KE = 1/2 * 2.45 * 1,225

KE = 1/2 * 3,001.25

KE = 1,500.63 Joules

Multiple Choice

A bicycle and a person with a total mass of 80 kg are traveling at a velocity of 7 m/s. What is their kinetic energy?

• 156,800 J

• 1,960 J

• 0.82 J

• 7,840 J

Multiple Choice

What is the kinetic energy of a 4kg shotput thrown with a velocity of 13m/s?

• 676 J

• 3.25 J

• 17J

• 338 J

Multiple Choice

How much kinetic energy does a moving 6 kg object have if it moves with a velocity of 3 m/s?

• 27 J
• 18 J
• 9 J
• 2 J

Multiple Choice

A cheetah can run briefly with a speed of 31.0 m/s. Suppose a cheetah with a mass of 47.0 kg runs at this speed. What is the cheetah’s kinetic energy?

• 1457 Joules

• 22,584 Joules

• 15 Joules

• 45,167Joules

Multiple Choice

What is the kinetic energy of a ball with a mass of 5kg rolling at 10m/s

• 50 J
• 5 J
• 250 J
• 25 J