Exam: Work, Power, and Machines

How much work is done by a forklift raising a 400 N crate from the ground to a height of 14 meters? (Show your work!)

How far would a ball have to roll if it had 40 N of force and was doing 170 J of work? (Show your work!)

How much power is required to push a box with a force of 10 N over 20 m in 30 seconds? (Show your work!)

How much work is done by a machine with a power output of 50,000 Watts if it has been running for a minute and a half? (Show your work!)

Using the definition of mechanical advantage, what is the output force when the input force is 4 N and the input distance is 16 meters while the output distance is 12 meters?

For the following objects, name the type of simple machine it is an example of (Answer only four of the following; If you answer more, only the first four will be graded):

ax

winch

spiral staircase

crowbar

ramp

scissors

Draw the following examples of levers.  For each:
a) Name which class of lever it is
b) Clearly label the input force, output force, and fulcrum (also use arrows to show the direction of the forces)

(Answer only four of the following; If you answer more, only the first four will be graded):

wheelbarrowhammer pulling a nail

pliarsnutcracker

drawbridge

Answer one of the following.  Circle the letter of the one you chose.
a) Use a diagram to explain how a pulley is like a lever.
b) Use a diagram to explain how a wedge is an inclined plane.

Give an example of compound machine and list and describe at least two simple machines that make up parts of the compound machine.  (Without descriptions, you cannot receive full credit.)
a)
b)