KINETIC ENERGY
TRUE/FALSE: The SI unit of Kinetic energy is JOULES
Kinetic Energy is not a scalar quantity
TRUE.
FALSE
The SI unit of Potential energy is not JOULES
FALSE
TRUE/FALSE: The SI unit of Power is WATT (W)
TRUE
What is Kinetic Energy?
Kinetic energy is the energy due to the motion of an object
TRUE/FALSE: The gravitation potential energy does not depend on the object's interaction with its environment
FALSE
TRUE/FALSE: Power is a scalar quantity
TRUE
State the Work-Kinetic energy theorem?
Can the kinetic energy of an object be negative? Explain your answer.
The net work done by a net force acting on an object is equal to the change in kinetic energy of the object: Wnet = change in KE
NO, because mass is always positive, and speed is squared
Define: Gravitational potential energy
Elastic Potential energy
Gravitational Potential energy is the energy due to the position (height) of an object.
Elastic Potential energy is the energy stored in a spring due to its extension or compression
Define: What is Power?
Power is the rate at which work is done or energy is transformed
If a bowling ball and a football are travelling at the same speed, which do you think has more kinetic energy? Explain
The bowling ball because it has more mass
Can the gravitational potential energy associated with an object be negative? Explain your answer.
Yes, because potential energy depends on the distance to an arbitrary level zero, which can be above or below the object
If Car A does work in less time than Car B, assuming they did the same work. Which car has more Power? Which car has less speed?
Car A has more Power
Car B has less speed
A 9.00 kg bowling ball moves at 5.00 m/s. How fast must a 2.45 g table tennis ball move in order to have the same kinetic energy as the bowling ball?
vt = 303 m/s
The staples inside a stapler are kept in place by a spring with a relaxed length of 0.38 m. If the spring constant is 50.0 N/m, how much elastic potential energy is stored in the spring when its length is 0.150 m?
PEelastic = 1.3 J
If an automobile engine delivers 50.0 hp of power, how much time will it take for the engine to do 6.40 ×105 J of work? (Hint: 1 hp = 746 watts.)
t = 17 s