Question

Qual a energia cinética, de uma bola de massa 0,9 Kg ao ser arremessada e atingir uma velocidade de 10m/s.

a) 55 J
b) 45 J
c) 48 J
d) 20 J

Answer 1

$\Large\displaystyle\text{ \begin{gathered} \hookrightarrow\boxed{\boxed{\bf{ E_C= 45~J }}} \end{gathered} }$

• Explicação:

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{m \cdot{v} {}^{2} }{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{0,9 \cdot10{}^{2} }{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{0,9\cdot100}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{90}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \boxed{\boxed{\sf{E_C =45 \: J }}} \end{gathered} }$