Question

1-Calcule a energia cinética de uma bola de massa 0,6 kg ao ser arremessada e atingir uma velocidade de 5 m/s. * A)7,5 J B)15 J C)1,5 J D)3 J

Answer 1

$E_c=\frac{1}{2}(0.6)(25)=0.3\cdot25=7.5\;J$

Letra: a)

Answer 2

$\Large\displaystyle\text{ \begin{gathered} \boxed{\boxed{\bf{ E_C= 7,5~J }}} \end{gathered} }$

Portanto:

$\Large\displaystyle\text{ \begin{gathered} \boxed{\boxed{\bf Letra~A}}\end{gathered} }$

• Explicação:

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

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{0,6\cdot5 {}^{2} }{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{0,6 \cdot25}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \sf{E_C = \dfrac{15}{2} } \end{gathered} }$

$\Large\displaystyle\text{ \begin{gathered} \boxed{\boxed{\sf{E_C =7,5 \: J }}} \end{gathered} }$