Definitions and more
Calculating PE
Calculating KE
Units
Miscellaneous
100
True or false: a ball on the ground has more potential energy than a ball on a hill.
False
100
What is the formula for calculating PE?
PE = mass x gravity x height
100
Which has more Kinetic Energy, a ball moving at 3 m/s or 5 m/s? Why?
5 m/s because it has a higher velocity
100
In calculating PE, and KE energy problems, what unit is used for height?
meters
100
What is energy?
The ability to do work.
200
How do you calculate speed?
Speed = distance / time
200
Calculate the PE of a rock that has a mass of 60 kg and is 10 m high.
5880 J
200
Determine the kinetic energy in a 7 kg ball thrown with a velocity of 20 m/s.
1400 Joules
200
In calculting PE and KE problems, what unit is mass?
Kilograms
200
Potential or kinetic: A parachutist about to jump.
Potential
300
What is the difference between kinetic energy and potential energy?
Kinetic energy is energy of motion. Potential energy is stored energy due to an object's position (height).
300
How much potential energy would a 3 kg table have if it's at the top of a hill 110 m high?
What is 3234 J
300
The computer weighs 3 kg and is thrown at a velocity of 5 m/s. Calculate the Kinetic energy.
37.5 Joules
300
In calculating KE and PE problems, what unit is velocity?
m/s
300
List 3 forms of potential energy
Gravitational, chemical, mechanical, nuclear, elastic
400
What is gravity? What is gravity always on Earth?
Gravity is the force that pulls us towards the ground. On Earth, gravity is always 9.8 m/s2
400
Which has more potential energy, a calculator on the ground or a calculator on the table 1.5 m high?
on the table. (greater height)
400
Calculate the kinetic energy of a 15 kg cart going 60 m/s.
27,000 J
400
What is the unit for Kinetic Energy?
Joules
400
List 3 forms of kinetic energy.
Motion (mechanical), heat (thermal), sound, light (radiant), electrical
500
What is height and what unit do we use for height?
How high, or tall something is, measured in meters.
500
Why might there be (slightly) more Potential Energy at the top of a rollercoaster than the total amount of energy at the very end of the ride?
Some energy is lost due to heat and sound.
500
Ms. Krieger's book weighs 5 kg and is dropped from the table 2 meters high. The pencil falls at a velocity of 10 m/s. What is the pencil's KE?
250 J
500
What unit is used for Potential Energy?
Joules
500
What is the law of conservation of energy?
Energy cannot be created nor destryoed, only changed in form.
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