Question

alguém que saiba pode me ajudar, pf.

Answer 1

1)
$E_M = E_C + E_P \\ E_M = m\frac{v^2}{2} + mgh \\ E_M = m(\frac{v^2}{2} + gh) \\ E_M = 2,5\times(\frac{2^2}{2} + 10\times40)\\ E_M = 1005 \ J$
2)
$E_{Mfinal}=E_{Minicial} \\ m\frac{v^2}{2} = mgh \\ \frac{v^2}{2} = gh \\ v^2 = 2gh \\ v = \sqrt{2gh} = \sqrt{2\times10\times5} \\ v = 10 \ m/s$
3)
$P_{basquete} = P_{volei} \\ m_{b}v_b = m_v v_v \\ 0,6\times v_b = 0,25\times30 \\ v_b = \frac{0,25\times30}{0,6} = 12,5 \ m/s$
4)
$I = \Delta P \\ \frac{(25+55)\times10}{2} = 78\times v_f - 78 \times 3 \\ 400 = 78v_f - 234 \\ v_f = \frac{400 + 234}{78} = 8,13 \ m/s$
5)
$I = \Delta P\\ F\Delta t = mv_f - mv_i \\ F\times 0,3 = 2,5 \times (-0,5) - 2,5\times 0,8 \\ F = \frac{-3,25}{0,3} = -10,83 \N \\ |F| = 10,83 \ N$