speed = distance travelled / time taken
acceleration = change in speed / time taken to change speed
(acceleration = (final speed - start speed) / time taken
If distance is measured in metres(m) and the time in seconds(s) then speed is measured in metres per second (m/s)
Acceleration (or deceleration) is caused by an unbalanced force, such as legs on a bike.
Velocity - is almost the same thing as speed, except is is a vector quantity. Velocity has a direction as well as a size. Eg - if a car is travelling at a constant speed in a straight line, then it has a constant velocity. But if it turns a corner, its velocity changes even though the speed remains constant. Similarly, a car travelling in the opposite direction has a negative velocity.
Terminal Velocity - is the fastest an object can move when all forces are working upon it (Eg. when a person jumps out of a plane, and then again when they fully open their parachute).
Kinetic Energy ---
KE = 0.5 x M x V
(J = 0.5 x Kg x (m/s)^2)
Any object that moves has kinetic energy.
Forces!!
Resultant force = Mass x Acceleration
Weight = mass x force of gravity (neutons, N)
Mass = how much of something there is (Kg)
1Kg - 10N
Work = force x distance
When a force moves an object, energy is transferred and work is done.
Change in potential energy = mass x gravitationl field strength x change in height
Or
Change in potential energy = weight x change in height
Hallelujah!! So glad that's over, but might have to post again laters :)
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