question archive Calculate the efficiency of a machine that has a useful energy output of 220 J when the work input is 300 J A 68
Calculate the efficiency of a machine that has a useful energy output of 220 J when the work input is 300 J A 68
Subject:Electrical EngineeringPrice: Bought3
Calculate the efficiency of a machine that has a useful energy output of 220 J when the work input is 300 J
A 68.0 kg diver is 2.30 m above the water, falling at speed of 3.10 m/s. Calculate her kinetic energy as she hits the water. (Neglect air friction)
A 46.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of?1.30 x 10^2 m/s from the top of a cliff 136 m above level ground, where the ground is taken
to be y = 0.
(a) What is the initial total mechanical energy of the projectile?
(b) Suppose the projectile is traveling 92.1 m/s at its maximum height of y = 312 m. How much work has been done on the projectile by air friction?
(c) What is the speed of the projectile immediately before it hits the ground if air friction does one and a half times as much work on the projectile when it is going down as it did when it was going up?
