Question

Um bloco de massa m= 2kg possuí energia cinética EC = 100j . Assim, a velocidade, em m/s, do bloco será de:

URGENTEEE 30 PONTOSS

Answer 1

$\mathbf{Dados}\Longrightarrow m=2\ \text{kg};\ K=100\ \text{J}.$

$\mathrm{A}\ \mathbf{energia\ cin\acute{e}tica}\ K\ \mathrm{\acute{e}\ dada\ por}\text{:}$

$\boxed{K=\dfrac{1}{2}mv^2}$

$\mathrm{Desse\ modo,\ a}\ \mathbf{velocidade}\ v\ \mathrm{pode\ ser\ isolada}\text{:}$

$v^2=\dfrac{2K}{m}\Longrightarrow \boxed{v=\sqrt{\dfrac{2K}{m}}}$

$\text{Logo:}$

$v=\sqrt{\dfrac{2(100)}{2}}=\sqrt{100}\ \therefore\ \boxed{v=10\ \text{m/s}}$