It's KE. Hi.
It's PE. Hi.
I'm The (Roller Coaster) Problem
It's ME
Energy Concepts
100
As the speed of an object increases, the kinetic energy for that object ________. This is a(n) ________ relationship.
increases, directly proportional
100
As the height of an object increases, the PE of the object _________. This is a(n) ____________ relationship.
increases, directly proportional
100
Calculate the PEg at Point 1.
1960 J
100
What is the mechanical energy of an object with 10 J of kinetic energy and 5 J of potential energy?
15 J
100
What happens to the total mechanical energy in a closed system?
The mechanical energy of a closed system is conserved. No energy is gained or lost.
200
What is the kinetic energy of an 5.0 kg object with a speed of 10 m/s?
KE = 250 J
200
Calculate the potential energy of a spring that is compressed 0.25 m if the spring constant is 10 N/m.
PEe = 0.3125 J
200
Calculate the ME at Point 1 if the object starts at rest.
ME = 1960 J
200
Draw a scenario when the total mechanical energy of an object would be 0.
An object that is not moving (at rest) and on the ground (h = 0).
200
If the mechanical energy of a system starts with 5,000 J and ends with 4,900 J, what do you know about the system and the mechanical energy?
The system is open and 100 J of mechanical energy is lost (or the total mechanical energy decreases).
300
Calculate the mass of an object traveling 5 m/s with a kinetic energy of 275 J.
m = 22 kg
300
An object is held at 15 m above the ground. If it has a PEg of 970 J, what is its mass?
m = 6.60 kg
300
Calculate the KE at Point 4
KE = 900 J
300
Draw a scenario that has both KE and PEg.
A moving object above ground.
300
For an open system, what are two examples of the total mechanical energy being not conserved?
Energy loss due to friction, air resistance, thermal energy, sound energy, or other types of energy.
400
The KE for a 25 kg object is 4000 J. What is the velocity this object?
v = 17.9 m/s
400
How far does a spring compress when it has a spring constant of 500 N/m and 9.5 J of potential energy?
x = 0.19 m
400
What is the velocity at Point 3 (h=0) assuming the entire roller coaster is a closed system.
v = 8.85 m/s
400
A 2000 kg roller coaster car has a speed of 4 m/s as it travels over a 12.5 m hill. Calculate the total mechanical energy of the roller coaster car on the hill.
ME = 261,000 J
400
An object sits on a table. As it falls off the table, the object's height _______, the PE _______, the KE _______, and the speed _______.
decreases, decreases, increases, increases.