Review sheet for Physics Test on 9/10/15

  1. What is work?

The product of force and distance when a force is used to move an object.

  1. What is the formula for work?

Work= Force x Distance

  1. You are working when you are holding a 50 pound weight in your hands? FALSE
  2. You are working when you are reaching down and lifting a book back on the bookshelf? TRUE
  3. In order to do work on an object, the _FORCE_you exert must be in the same direction as the object’s motion.
  1. The fixed point which a lever pivots around is a FULCRUM.
  1. What piece of equipment would you use to check the amount of force used if you were pulling a block across different surfaces? A SPRING SCALE
  1. What has more friction a smooth surface or a rough surface?Rough
  1. Name the simple machines:

INCLINED PLANEWHEEL AND AXLEWEDGE

LEVERGEARS

SCREWPULLEY

  1. What do machines do?

MAKES OUR LIVES EASIER, FOR EXAMPLE IT CAN ALLOW YOU TO USE LESS FORCE TO MOVE AN OBJECT BY USING A RAMP.

  1. Does a machine change the amount of work we do?

NO, THE WORK IS THE SAME.

  1. What is a compound machine? Give two examples.

A MACHINE THAT USES TWO OR MORE SIMPLE MACHINES. EXAMPLES: BICYCLE, SCISSORS, ETC.

  1. What is a device with toothed wheels that fit into one another called? Where would you find one?

GEARS, YOU CAN FIND THEM INSIDE OF A WATCH, IN A 10 SPEED BIKE, ETC.

  1. What is an inclined plane wrapped around a cylinder called? Give an example.

SCREW. UNSCREWING A JAR LID, SCREW, SPRING, WIRE ON SPIRAL NOTEBOOK, ETC.

  1. The fixed point a lever pivots around is called? Give an example of the simple machine.

FULCRUM. EXAMPLE OF LEVERS: SEESAW, USING A SPOON TO PRY OPEN A CAN OF PAINT, USING A BROOM, ETC.

  1. When you raise or lower the blinds in your home, you are using which simple machine?

PULLEY

  1. A ramp or stairs are an example of which simple machine?

INCLINED PLANE

  1. When you raise or lower aflagpole, which simple machine are you using?

PULLEY

  1. Which simple machine are you using when you are turning a doorknob?

WHEEL AND AXLE

  1. When you bend your arm and lift a bag, the elbow is acting as a _FULCRUM_for the forearm bone.
  1. Which part of your body is shaped like wedges? INCISORS
  1. What is the most important force that made the marble come to a stop? FRICTION
  1. Explain how a knife can be a compound machine.

THE SHARP EDGE OF THE KNIFE IS THE WEDGE, WHEN YOU BRING IT UP AND DOWN TO CUT IT IS ALSO A LEVER.