Answer:
0.04kg
Explanation:
Explanation in pics:
The formula for kinetic energy is KE = 1/2mv². So now the question asks for the mass, not KE. So we need to rearrange the formula so that we are calculating the mass. So, the formula for mass is m=KE/(1/2v²). Now we just substitute the values into the formula. Then just follow what it shows in the pic
