Kinetic Energy 1

Question 1

What is kinetic energy?

Answer 1

Kinetic energy is the energy stored in moving objects. Stationary objects have no kinetic energy

Question 2

A tennis ball is travelling at 50 m / s and has a kinetic energy of 75J. Calculate the mass of the tennis ball.

Answer 2

Equation: 0.5 x m x v^2

75J = 0.5 x m x 50^2

75J = 1250 x m

m = 0.06 kg

Question 3

A car with a mass of 700kg is moving with a speed of 20 m / s. Calculate the kinetic energy of the car.

Answer 3

Equation: 0.5 x m x v^2

0.5 x 700 x 20^2 = 140,000 J

140 kJ

Question 4

How can we get to kj from J?

Answer 4

We can get to kj by dividing the amount of joules by 1000.