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Potential Energy
Kinetic Energy
Work
Power
Definitions
100
9.8 m/s2
What is gravity
100
The unit for energy.
What is Joules (J)
100
The unit for force.
What is Newtons (N)
100
The unit for power.
What is Watts (W)
100
Stored energy
What is potential energy
200
The equation for potential energy.
What is PE = mgh
200
The equation for kinetic energy.
What is (mv^2)/2
200
The equation for work.
What is W = F x d
200
The equation for power.
What is P = W/T
200
Energy in motion
What is kinetic energy
300
Dave holds a 6 kg bowling ball 3.5 m up in the air. What is the potential energy?
What is 6 x 9.8 x 3.5 = 205.8 J
300
A 33 kg cheetah chases an antelope across the African plain at a speed of 65 m/s. What is the cheetah's kinetic energy?
What is (33 x 65^2)/2 = 69,712.5 J
300
Sally lifts a bowling ball with a force of 55 N off the floor a distance of 3.5 m. How much work did she do?
What is 55 x 3.5 = 192.5 J
300
A boy does 3500 J of work on the oars in a canoe in 145 s. What is his power?
What is 3500/145 = 24.1 W.
300
The rate at which work is done.
What is power
400
A boulder with a mass of 450 kg is sitting on a cliff 95 m tall. What is the boulder's potential energy?
What is 450 x 9.8 x 95 = 418,950 J
400
A 50 kg model runs across a store at a speed of 27 m/s. What is her kinetic energy?
What is (50 x 27^2)/2 = 18,225 J
400
Jason lifts an 80 N pumpkin a distance of 3 m. How much work does he do?
What is 80 x 3 = 240 J
400
Cindy does 1600 J of work moving boxes in 45 s. How much power does she exert?
What is 1600/45 = 35.6 W
400
The quantity of energy transferred by a force when it is applied to a body and causes that body to move in the direction of the force.
What is work
500
A 17.5 kg cat runs up a tree that is 8.7 m high. What is the cat's potential energy?
What is 17.5 x 9.8 x 8.7 = 1492.05 J
500
Kelly throws a 3.5 kg ball at a speed of 15 m/s. What is the kinetic energy?
What is (3.5 x 15^2)/2 = 393.75 J
500
A golfer does 14,000 J of work to move a golf ball 200 m down the fairway. How much force does he exert?
What is 14,000/200 = 70 N
500
A football player presses a 250 N weight 1.3 m in the air in 2.5 s. What is his power? (hint: you have to find work FIRST)
What is 250 x 1.3 = 325 J, 325/2.5 = 130 W
500
An action exerted on a body in order to change the body's state of rest or motion.
What is force