Question

A 0.5 kg object is moving with a velocity of 10 m/s. What is its kinetic energy?

• A. \( 25 \, \text{J} \)
• B. \( 100 \, \text{J} \)
• C. \( 200 \, \text{J} \)
• D. \( 50 \, \text{J} \)

Hint:

Kinetic energy depends on the square of the velocity. Even a small change in velocity can lead to a large change in kinetic energy.

Answer 1

The Correct Option is A

To find the kinetic energy of an object, we use the formula for kinetic energy, which is given by:

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

where:

• \( m \) is the mass of the object in kilograms
• \( v \) is the velocity of the object in meters per second

Given that the mass \( m = 0.5 \, \text{kg} \) and the velocity \( v = 10 \, \text{m/s} \), we can substitute these values into the formula:

\[ KE = \frac{1}{2} \times 0.5 \, \text{kg} \times (10 \, \text{m/s})^2 \]

First, calculate the square of the velocity:

\[ (10 \, \text{m/s})^2 = 100 \, \text{m}^2/\text{s}^2 \]

Then, multiply by the mass and divide by 2:

\[ KE = \frac{1}{2} \times 0.5 \times 100 \]

\[ KE = 0.25 \times 100 = 25 \, \text{J} \]

Thus, the kinetic energy of the object is \( \boxed{25 \, \text{J}} \), indicating that there was an error in the provided solution options.