Question

A car with a mass of 1400 kg is being driven along the motorway at 30 m/s. Calculate the kinetic energy of the car

Answer 1

Answer:

.I'm going to assume that by speed, you meant velocity.

The formula for KE is KE=1/2mv^2

So input the values we know:

KE=1/2⋅1200⋅20^2

KE=1200⋅400/2

KE=480000/2

KE=240000

The unit for energy is Joules(J) so the kinetic energy of the car is 240000J

Answer 2

Answer:

6.3 \cdot 10^5 J6.3⋅10

5 J

Explanation

The kinetic energy of an object is given by

K=\frac{1}{2}mv^2K=

2

1

mv 2

where

m is the mass of the object

v is its speed

For the car in this problem,

m = 1400 kg

v = 30 m/s

Therefore, the kinetic energy of the car is

K=\frac{1}{2}(1400)(30)^2=6.3 \cdot 10^5 JK=

2

1

(1400)(30)

2

=6.3⋅10

5

J