motion

 Motion:

• motion is related with moving bodies. physical quantities, such as length, distance and time are linked with motion. 

Distance: a length between two points with an S.I unit of m (meters) [can never be 0]

Time: a duration between two events, with an S.I unit of s (seconds.)

Speed: distance travelled in unit time. formula: speed = distance/time or v=s/t          (v representing speed, s representing distance and t representing time.)

speed and distance are scalar quantities, they only have a magnitude, and no direction.

average speed: total distance travelled/total time taken. 

velocity: change in displacement per unit time.                                                                         • velocity is basically speed, but the only difference is that it has a direction. 

displacement: distance which moves in a stated direction.

displacement and velocity are vector quantities, they both have a magnitude and a direction.

acceleration: change in velocity per unit time, basically how quickly something speeds up and slows down.                                 • when the velocity of an object changes, we say the object accelerates.                                  formula: change in velocity/time taken (∆v/t)

• when the velocity increases, the acceleration is positive.                                       • when the velocity decreases, acceleration is negative, this is also known as retardation or deceleration. 

- when the velocity/speed of a body is uniform or constant, it moves in a steady and straight line.                                                   - when the velocity of a body is not uniform or constant, it is moving in a curved path.

• the speed of an object can be represented by distance - time graph.                                     - the gradient is speed.

• the acceleration of an object can be shown on a speed-time graph.                                         - the gradient is acceleration.

for further clarity, refer to cognito's videos on these topics :)