Ch. 13 Phy. Science

Work done on an object depends on

• any force applied to the object.

• the force parallel to the object’s movement.

• the force perpendicular to the object’s movement.

• the amount of time that the force is applied.

A driver pushes on a car with a force of 8000 N for 15 s but is unable to move it. How much work is done?

• 0 J

• 533 J

• 8000 J

• 120 000 J

A machine with a mechanical advantage of greater than 1 will multiply __________.

• distance

• force

• work

The simple machine shown in the image at right is an example of a

• first-class lever.

• second-class lever.

• third-class lever.

• wheel and axle.

In a second-class lever,

• the fulcrum is between the input force and the output force.

• the input force and fulcrum are in the same location.

• the input force is between the fulcrum and the output force.

• the output force is between the input force and the fulcrum.

Using a first-class lever to move a rock, you exert 60 N of force as you move the lever 1 m. The lever applies a force of 200 N to move the rock 0.2 m. What is the efficiency of the lever?

• 25%

• 33%

• 50%

• 67%

Tags

NGSS.MS-PS2-1

What is the IMA of a gear system if your input gear has 54 teeth and the output gear has 24 teeth?

• 0.44

• 1.25

• 1.8

• 2.25

Tags

NGSS.MS-PS2-1

Window blinds are most likely to use which simple machine for their operation?

• gears

• a pulley

• a screw

• a wedge

The simple machine shown below has an IMA of __________.

• 0.5

• 1.0

• 2.0

• 4.0

Tags

NGSS.MS-PS2-2

The mechanical advantage of an inclined plane depends on the __________ of the plane.

• height

• length

• steepness

• thickness