Question

A car is traveling with a velocity of 40 m/s and has a mass of 1120 kg. The car has ___________energy. Calculate it.

Answer 1

To find the kinetic energy (KE) of the car, we can use the kinetic energy formula:

\[
KE = \frac{1}{2}mv^2
\]

where:
- \( m \) is the mass of the car (in kilograms),
- \( v \) is the velocity of the car (in meters per second).

Given:
- \( m = 1120 \, \text{kg} \)
- \( v = 40 \, \text{m/s} \)

Now, we can substitute the values into the formula:

\[
KE = \frac{1}{2} \times 1120 \, \text{kg} \times (40 \, \text{m/s})^2
\]

Calculating \( (40 \, \text{m/s})^2 \):

\[
(40 \, \text{m/s})^2 = 1600 \, \text{m}^2/\text{s}^2
\]

Now substituting back into the kinetic energy formula:

\[
KE = \frac{1}{2} \times 1120 \times 1600
\]

Calculating \( \frac{1}{2} \times 1120 \):

\[
\frac{1}{2} \times 1120 = 560
\]

Now multiply by 1600:

\[
KE = 560 \times 1600 = 896000 \, \text{J}
\]

So, the car has a kinetic energy of **896,000 joules** (or 896 kJ).