Question

a 50 - kilogram student is running and has 225 joules of kinetic energy. the students speed is meters/second. find the velocity of the student using $ke=\frac{1}{2}mv^{2}$. type the correct answer in the box.

Explanation:

Step1: Rearrange kinetic - energy formula

Given $KE=\frac{1}{2}mv^{2}$, we can solve for $v$. First, multiply both sides by 2 to get $2KE = mv^{2}$. Then, divide both sides by $m$: $v^{2}=\frac{2KE}{m}$. Finally, take the square - root of both sides: $v=\sqrt{\frac{2KE}{m}}$.

Step2: Substitute values

We know that $m = 50$ kg and $KE=225$ J. Substitute these values into the formula: $v=\sqrt{\frac{2\times225}{50}}=\sqrt{\frac{450}{50}}=\sqrt{9}$.

Step3: Calculate the result

Since $\sqrt{9}=3$, the speed of the student is 3 m/s.

Answer:

3