just give me the answer

Determine the kinetic energy of a 625-kg roller coaster car that is moving with a speed of 18.3 m/s.

1 answer

The kinetic energy (KE) can be calculated using the formula:

\[ KE = \frac{1}{2} m v^2 \]

Where:

  • \( m \) is the mass (625 kg)
  • \( v \) is the speed (18.3 m/s)

Plugging in the values:

\[ KE = \frac{1}{2} \times 625 , \text{kg} \times (18.3 , \text{m/s})^2 \]

Calculating it step by step:

  1. Calculate \( (18.3 , \text{m/s})^2 = 334.89 , \text{m}^2/\text{s}^2 \)
  2. Then, calculate \( \frac{1}{2} \times 625 \times 334.89 = 104,099.0625 , \text{J} \)

Rounding to three significant figures, the kinetic energy is:

104,000 J (joules).