1 - Energy Storage
2 - Work and Energy Trans
3 - Power
4 - Energy Conservation
100
Energy of motion.
What is Kinetic Energy
100
Hulky and Bulky challenge each other to a race up a flight of stairs (∆h = 4.0 m). Hulky, whose mass is 120 kg, makes the climb in 3.0 s; while Bulky, 150 kg, took 4.0 s to make the climb.
This is the amount of E_grav that Bulky has at the top.
What is 5886 Joules?
100
A water heater in Mr. Huang’s house uses an average of 250 Watts of electrical power.
How much energy (in Joules) would the water heater use during one month?
What is 21.6 x 106 Joules?
100
A 100 kg car has a total of 30,000 J of gravitational energy at point A. It moves down a frictionless track and comes to a stop as it compresses a spring at point D.
This is the amount of kinetic energy does the car has at point C.
This is the amount of kinetic energy does the car has at point C.
What is 30,000 J
200
Energy stored in the compression or stretch of a spring.
What is Elastic Energy
200
Hulky and Bulky challenge each other to a race up a flight of stairs (∆h = 4.0 m). Hulky, whose mass is 120 kg, makes the climb in 3.0 s; while Bulky, 150 kg, took 4.0 s to make the climb.
This is the power output of Hulky.
What is 1570 Watts?
200
How many kilowatt-hours of energy does a 350 Watt high-end gaming computer use when left on continuously for 45 hours? (This is about 1.5 hrs for every day in one month).
What is 15.75 kWh?
200
A 100 kg car has a total of 30,000 J of gravitational energy at point A. It moves down a frictionless track and comes to a stop as it compresses a spring at point D.
This is the velocity of the car at point B.
This is the velocity of the car at point B.
What is 20 m/s?
300
The units of "k" - the spring constant.
What are N/m
300
You and your devious friends push a 1500 kg car along a level road, accelerating it from rest. The pushers transfer 6000 J of energy into the system and 2000 J of that is dissipated by friction.
How fast will the vehicle be traveling after the push?
What is 2.31 m/s?
300
A spring whose spring constant is 80 N/m is compressed 0.50 m. What is the maximum speed it can give to a 500 g ball?
What is 6.3 m/s?
400
A 2 kg mass is lifted 4 m above the ground. Find the change in gravitational energy.
What is 78.48 Joules
400
40 Joules of energy are expended to drag a classmate 2 m across a floor at constant velocity. Find the frictional force on the classmate.
What is 20 Newtons?
400
The compressed spring with 0.67 J of energy launches the 80 g block upward. If the block’s velocity is 0.65 m/s when it is 42 cm high. This is the amount of energy lost.
What is 0.32 J?
400
In the final situation below, the 8.0 kg box has been launched with a speed of 10 m/s across a frictionless surface.
This is the energy stored in the spring.
This is the energy stored in the spring.
What is 400 Joules?
500
A physics student pushes a 5 kg block with 20 N of force across a surface. This is the amount of work done to the block after moving 3 meters.
What is 60 Joules?
500
How much time would it take a 6000 Horsepower train locomotive to use the 132 million Joules of energy in a gallon of diesel fuel? (1 Hp = 746 Watts)
What is 29.5 seconds?
500
In the final situation below, the 8.0 kg box has been launched with a speed of 10 m/s across a frictionless surface.
This spring was compressed 4.0 m. This is the spring constant.
This spring was compressed 4.0 m. This is the spring constant.
What is 50 N/m?