Question

qual energia cinetica de uma particula  de 5000g cuja velocidade vale 72 km/h ?

Answer 1

Formula: Ec:MV2/2

5000g : 5kg
 72 divide po 3.6: 20
ec: 5.20(2) / 2 (ao quadrado)
ec: 2000 / 2
ec: 1000

Answer 2

$\sf m=5000\,g$

$\sf m=5\,kg$

$\sf v=72\,km/h$

$\sf v=20\,m/s$

$\sf E_c=\dfrac{1}{2}\cdot m\cdot v^2$

$\sf E_c=\dfrac{1}{2}\cdot5\cdot20^2$

$\sf E_c=2{,}5\cdot400$

$\boxed{\boxed{\sf E_c=1000\,J}}$