(a) KE = m•v²/2 = 3.8•(56)²/2 =5958.4 J.
(b) a =v²/2•s = (56)²/2•22 = 71.27 m/s².
F=m•a = 3.8•71.27 = 270.8 N
A steel ball has a mass of 3.8 kg and rolls along a smooth, level surface at 56 m/s.
(a) Find its kinetic energy.
1 I got 404.32J bu it doset work
(b) At first, the ball was at rest on the surface. A constant force acted on it through a distance of 22 m to give it the speed of 56 m/s. What was the magnitude of the force?
2 N
-unsure how to calculate this(do you use your first answer?)
1 answer