Question

What is the kinetic energy of a body of mass $ 2 \, \text{kg} $ moving with a velocity of $ 5 \, \text{m/s} $?

• A. \( 25 \, \text{J} \)
• B. \( 10 \, \text{J} \)
• C. \( 50 \, \text{J} \)
• D. \( 5 \, \text{J} \)

Hint:

Remember: Kinetic energy is always positive and is given by \( KE = \frac{1}{2} m v^2 \).

Answer 1

The Correct Option is A

Calculate the Kinetic Energy of a Body

We are given the following data:

• Mass of the body \( m = 2 \, \text{kg} \)
• Velocity of the body \( v = 5 \, \text{m/s} \)

Step 1: Recall the formula for kinetic energy

The formula for kinetic energy is: \[ KE = \frac{1}{2} m v^2 \]

Step 2: Substitute the given values

\[ KE = \frac{1}{2} \times 2 \, \text{kg} \times (5 \, \text{m/s})^2 \]

Step 3: Simplify the calculation

\[ KE = \frac{1}{2} \times 2 \times 25 = 25 \, \text{J} \]

Conclusion:

The kinetic energy of the body is \( 25 \, \text{J} \).

The correct answer is:

Option 1: 25 J