Work, Energy, Heat and Simple Machines Review

How much work is done by a 50 N force pushing a chair 10 m across the floor?

• 100 J

• 40 J

• 0.25 J

• 500 J

Tags

NGSS.HS-PS3-2

How much work does a 0.2-Watt device do in 10 seconds?

• 2.0 J

• 50 J

• 16 J

• 0.5 J

The quantity that measures the rate at which work is done is ____.

• advantage

• efficiency

• power

• work

The law of conservation of energy states that energy in a system can change forms but can never be created or destroyed.

• is the product of KE and PE.

• can change forms but never created nor destroyed

• cannot change form but never created nor destroyed

• allows matter to move

Tags

NGSS.MS-PS3-2

NGSS.MS-PS3-4

NGSS.MS-PS3-5

An example of radiant energy.

• Energy from movement.

• Energy from splitting of the nucleus of an atom.

• Energy from food.

• Energy from the Sun.

Tags

NGSS.MS-ESS2-4

Which of these machines is a first class lever when used in the normal manner?

• Wheelbarrow

• Fishing pole

• Scissors

• Bicycle

Which of these machines is a second class lever when used in the normal manner?

• Wheelbarrow

• Rake

• Pliers

• Bicycle

Which of these machines is a compound machine?

• Wheelbarrow

• Rake

• Pliers

• Bicycle

Which of these machines is a third class lever when used in the normal manner?

• Nutcracker

• Baseball bat

• Pliers

• Car

The ____ of a machine is the number of times it multiplies the effort force. (Use your equations as a guide)

• efficiency

• ideal mechanical advantage

• effort force

• mechanical advantage