| Question | Answer |
| energy | a property that enables something to do work. |
| Work | occurs when a force is applied to an object over a distance, and the object moves in response to the force. |
| If something has the ability to cause a change in motion, it is has _______. | energy |
| Energy can cause ____ to be done, so when we see work done, we see evidence of energy. | work |
| A spring scale is used to measure _____. | force |
| Force is measured in SI units called ____ | newtons |
| simple machine | a device that helps reduce the amount of force required to do work. |
| A simple machine allows the user to apply a smaller force over a ______ distance to move an object. | larger |
| Simple machines can also change the _____ of the force applied. | direction |
| lever | a rigid bar or board that is free to move around a fixed point |
| fulcrum | the fixed point about which a lever pivots |
| The _____ may be placed at different locations along the lever. | fulcrum |
| By increasing the ________ from the fulcrum to the point where the effort force is applied, a lever can reduce the amount of force required to lift the weight. | |
| By decreasing the distance the _____ is from the fulcrum, a lever can reduce the amount of force required to lift a weight. | weight |
| pulley | a grooved wheel with a rope running along the groove. |
| _____ can change the amount and/or the direction of the effort force applied. | Pulleys |
| _______ pulleys are used to reduce the effort force. | movable |
| A single fixed pulley changes only the ______ of the force. | direction |
| inclined plane | a sloping surface that reduces the amount of force required to lift an object. |
| An inclined plane can be designed to reduce the force needed to lift a weight by ______ the length of the ramp or _______ the height of the ramp. | increasing; decreasing |
| Scissors, a crowbar, tweezers, a broom, a wheelbarrow, and bottle opener are all examples of a simple machine called a _______. | lever |
| ____ pulleys can be found on a flag pole or window blinds. | Fixed |
| ____ pulleys can be found on cranes and as part of a block & tackle system. | Movable |
| fixed pulley | a pulley that is attached to a structure |
| movable pulley | a pulley that is not attached to a structure |
| wedge | an inclined plane that can move |
| Knives and nails are examples of ______. | wedges |
| screw | an inclined plan wrapped around a post or cylinder. |
| Wheel and axles | consist of two circular objects that rotate. |
| Door knobs, steering wheels, screwdrivers, and gears are all examples of simple machines called ____. | wheel & axles |
| Complex machines | consist of two or more simple machines. |
| Complex machines are also known as _____ ______. | compound machines |
