8. Responde às seguintes questões.
Um cubo de volume 5 cm foi colocado num líquido de massa volúmica 780 kg/m². Sabendo que
o cubo ficou totalmente imerso, responde às seguintes questões. (g = 10 m/s)
a) Qual o valor da impulsão sofrida pelo cubo?
b) Que Lei utilizaste para responder à alínea anterior?

An athlete swings a ball, connected to the end of a chain, in a horizontal circle. the athlete is able to rotate the ball at the rate of 8.13 rev/s when the length of the chain is 0.600 m. when he increases the length to 0.900 m, he is able to rotate the ball only 6.04 rev/s. (a) which rate of rotation gives the greater speed for the ball? 6.04 rev/s 8.13 rev/s (b) what is the centripetal acceleration of the ball at 8.13 rev/s? m/s2 (c) what is the centripetal acceleration at 6.04 rev/s? m/s2