Question

alguem me ajuda com essa questão!!

Answer 1

$W = \Delta E_c \\ W = m\frac{v_{f}^2}{2} - m\frac{v_{i}^2}{2}\\ W = \frac{m}{2}(v_{f}^2 - v_{i}^2) \\ W = \frac{5}{2}(15^2 - 5^2) = 2,5(225-25) = 500 \ J$