To find out how fast the man is running, we can use the formula for kinetic energy:

$KE = \frac{1}{2} m v^2$

Where:

• $KE$ is the kinetic energy (400 J),
• $m$ is the mass (80 kg),
• $v$ is the velocity (which we need to find).

We can solve for velocity $v$:

$v = \sqrt{\frac{2 KE}{m}}$

Let’s plug in the values and calculate the velocity.import math

Given values

KE = 400 # Kinetic energy in joules m = 80 # Mass in kilograms

Solving for velocity

v = math.sqrt(2 * KE / m) vThe man is running at approximately $3.16 \, \text{m/s}$.

Would you like more details or have any questions?

Here are 5 related questions for further exploration:

1. What is the relationship between mass and kinetic energy?
2. How does doubling the velocity affect the kinetic energy?
3. What would be the kinetic energy if the man were running twice as fast?
4. How can we calculate the momentum of the man?
5. What are some real-world examples of kinetic energy?

Tip: The kinetic energy increases with the square of the velocity, meaning a small change in speed results in a larger change in energy!