The kinetic energy (KE) of an object can be calculated using the formula:
\[ KE = \frac{1}{2}mv^2 \]
where:
- \( m \) is the mass of the object (in kilograms),
- \( v \) is the speed of the object (in meters per second).
For the freight train:
- \( m = 2000 \) kg
- \( v = 25 \) m/s
Plugging in the values:
\[ KE = \frac{1}{2} \times 2000 , \text{kg} \times (25 , \text{m/s})^2 \]
Calculating \( (25 , \text{m/s})^2 \):
\[ (25 , \text{m/s})^2 = 625 , \text{m}^2/\text{s}^2 \]
Now substitute that back into the KE equation:
\[ KE = \frac{1}{2} \times 2000 , \text{kg} \times 625 , \text{m}^2/\text{s}^2 \]
\[ KE = 1000 \times 625 \]
\[ KE = 625,000 , \text{J} \]
Therefore, the kinetic energy of the train is 625,000 J.
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