Question

Determine a velocidade de um corpo de massa 100Kg e que possui energia cinética igual a 1250J?

Answer 1

$\displaystyle \mathsf{m = 100 \: Kg}\\ \displaystyle \mathsf{E_c = 1250 \: J}\\ \displaystyle \mathsf{V = ?}\\ \\ \displaystyle \mathsf{E_c = \frac{m.v^2}{2}}\\ \\ \displaystyle \mathsf{1250 = \frac{100.v^2}{2}}\\ \\ \displaystyle \mathsf{1250 = 50.v^2}\\ \\ \displaystyle \mathsf{v^2 = \frac{1250}{50}}\\ \\ \displaystyle \mathsf{v^2 = 25}\\ \displaystyle \mathsf{v = \sqrt{25}}\\ \displaystyle \mathsf{v = 5 \: m/s}\\ \\ \displaystyle \boxed{\mathsf{Resposta: 5 \: m/s}}$

Answer 2

$E_{c} = \frac{m* v^{2} }{2} \\ \\ 1250 = \frac{100 v^{2} }{2} \\ \\ 100 v^{2} = 2500 \\ \\ v^{2} = 25 \\ \\ \boxed{v = 5m/s}$