Unit 4: Force & Motion

Speed

• Distance an object travels per unit of time.

• The rate at which an object accelerates.

• The total distance covered by an object.

• The time taken to cover a specific distance.

3rd Class Lever

• The input force is located between the output force and fulcrum - i.e. a baseball bat.

• The fulcrum is located between the input force and output force - i.e. a seesaw.

• The output force is located between the input force and fulcrum - i.e. a wheelbarrow.

• The input force is applied at one end, and the output force is at the other end - i.e. a crowbar.

2nd Class Lever

• The output force is located between the input force and fulcrum - i.e a wheelbarrow.

• The input force is located between the output force and fulcrum - i.e a seesaw.

• The fulcrum is located between the input force and output force - i.e a pair of scissors.

• The output force is located at one end, and the input force is at the other end - i.e a crowbar.

Distance

• An amount of space between two things or people.

• A measure of time taken to travel a certain path.

• The speed at which an object moves.

• The weight of an object in relation to gravity.

Simple Machines

• Machine that requires multiple movements to operate.

• Machine that does work with only one movement - lever, pulley, wheel and axle, inclined plane, screw and wedge.

• Machine that can only lift heavy objects.

• Machine that is used for complex tasks.

1st Class Lever

• The fulcrum is located between the input and output forces - i.e. a screwdriver opening paint can.

• The fulcrum is located at one end, with the input force applied at the other end - i.e. a seesaw.

• The fulcrum is located at the input force, with the output force applied at the other end - i.e. a wheelbarrow.

• The fulcrum is located in the middle, with both forces applied at the ends - i.e. a pair of scissors.

Displacement

• The distance traveled by an object in a straight line.

• The amount by which a thing is moved from its original position.

• The total path length covered by an object during its motion.

• The change in velocity of an object over time.

Mass

• The amount of matter in an object.

• The weight of an object in a vacuum.

• The volume of an object measured in liters.

• The density of an object calculated by mass divided by volume.

Velocity

• Speed of a moving object only.

• Direction of a moving object only.

• Speed and direction of a moving object.

• Acceleration of a moving object.

Mechanical Advantage (MA)

• Ratio of the output force exerted by a machine to the input force applied to the machine.

• The measure of how much a machine multiplies force.

• The difference between input and output forces in a machine.

• The efficiency of a machine in converting energy.