Energy Calculations

Gimme the Secret Formuler

100

What is the formula for calculating Kinetic Energy?

KE = 1/2mv²

200

What are the TWO formulas used for calculating GPE?

GPE = mgh = Wh

300

What would the formula look like to calculate for the height of an object if given GPE and the mass?

h = GPE/mg = GPE/W

400

What would the formula look like for calculating the mass of an object if given the KE and the velocity?

m = 2KE/v²

500

What would the formula look like for calculating the velocity of an object if given the KE and the mass?

v = √(2KE/m)

Energized

100

Which energy is associated with moving objects?

Kinetic Energy

200

Which energy is associated with non moving objects and their position above the earth?

Gravitational Potential Energy

300

Which energy is the result of friction between two objects?

Thermal Energy

400

What is the combination of Kinetic and Potential energy known as?

Mechanical Energy

500

Fill in the blanks:

Energy cannot be _______ nor _______, but _______ into different states.

Energy cannot be created nor destroyed, but transforms into different states.

Quick Maffs

100

What is the potential energy of an object with 1 kg of mass resting at 1 m height? (Remember: g = 9.8 m/s²)

9.8 J

200

What is the kinetic energy of an object with 1 kg of mass traveling at 2 m/s?

2 J

300

What is the height of an object with 1 kg of mass and a potential energy of 98 J

10 m

400

What is the mass of an object traveling at a velocity of 2 m/s with 8 J of kinetic energy?

4 kg

500

What is the velocity of an object with a mass of 2 kg traveling with 16 J of kinetic energy?

4 m/s

Not So Quick Maffs (All worth double!)

100

An object with a weight of 500 N rests at a height of 75 m. What is its GPE?

GPE = Wh

37,500 J

200

An object with 9000 J of GPE sits on top of 33 m cliff. What is its mass to the nearest 10th?

27.8 kg

300

An object with a weight of 588 N travels with a velocity of 10 m/s. What is its kinetic energy?

6000 J

400

A bullet with a mass of 0.05 kg travels with 36,000 J of kinetic energy. What is its velocity?

1,200 m/s

500

A roller coaster with a weight of 7,350 N rests at the top of a hill on the track with 250,000 J. When it is half way down the hill, 10% of the total energy in the system has been converted to thermal energy due to friction. What velocity is the coaster moving at when it is exactly halfway down the hill? Round to the nearest 10th.

m = W/g = 750 kg

Mechanical Energy = Total x .9 = 225,000 J

Half way point means 1/2 ME = KE = PE

KE = 112,500 J

v = √(2KE/m) = 17.3 m/s