Work Power and Simple Machines

What is the function of a lever?

• To oppose motion between surfaces.

• To move objects in the same direction as the applied force.

• To pivot or rotate about a point.

• To wrap around a cylinder or post.

What is a pulley?

• A circular object that rotates on a central axle.

• A wheel with teeth that meshes with a chain or belt.

• A grooved wheel with a rope or cable wrapped over it.

• Two circular objects of different sizes that rotate independently.

If the object does not move then what is happening

• nothing

• work

• power

• no work is being done on the object

Tags

NGSS.HS-PS3-2

Which of the following examples has NO work being done? (Choose all that apply)

• An archer stretches her bowstring.

• An ant carries a leaf cutting from a tree to his colony

• An athlete does push-ups on the ground

• A book sits on the shelf

What does a wheel and axle consist of?

• Two circular objects of the same size that rotate independently.

• Two circular objects of different sizes that are attached and rotate together.

• A grooved wheel with a rope wrapped around it.

• A circular object with spokes that connect to a central point.

units for work are

• newtons

• joules

• meters

• seconds

if you push a cart with a force of 60 N for 2 m... how much work have you done

• 120 J

• 30 J

• 120 N

• 30 N

Tags

NGSS.MS-PS3-5

What is the formula for work?

• Force = work x distance

• Distance = force x work

• Work = force x distance

• Work = force x mass

Fred kicks a ball with a force of 20N to George, who is 5M away. How much work was done to the ball?

• 25J

• 100J

• 4J

• 75J

If 40N of force is applied to Rollo Koster's 10 kg cart over a distance of 50 meters, how much work is done?

• 8000J

• 8000N

• 4000J

• 2000J

Tags

NGSS.MS-PS3-5