Forces of motion

Speed:

• Average speed is calculated by dividing the total distance by the time. The gradient of a distance-time graph is equal to the speed of the object. It can be calculated by doing rise/run

• Average speed= distance moved/time

Graphs:

• Distance time graphs: If an object is travelling at a steady speed, Its distance-

  time graph will be a straight line going upwards. However, if its speed is changing the line of the graph will be curved. The gradient is velocity

• Velocity time graphs: If an object is travelling at a steady speed, its velocity-time graph will be an horizontal straight line. On the other hand if its speed is changing the line of the graph will be curved. The gradient is acceleration

Velocity:

• Velocity= displacement/time

• Displacement is defined as the change in position of an object.

Key words:

• The distance an object has travelled is the area of the graph

• Velocity: vector

• Speed: scalar

• Distance: speed x time

Acceleration:

• change in velocity(meters/seconds)/time (seconds)

• a=(v-u)/t

SUVAT equations:

1. s=(v+u)/2 x t

2. v²=u²+2as

• s= displacements

• a= acceleration

• v= final velocity

• u= initial velocity

Forces:

• Friction:

  • Force that opposes motion

  • Air resistance is a form of friction

• Electrostatic force:

  • Force between two charged particles

• Tension:

  • Force that is acting through a stretched object

• Upthrust:

  • Force pushing up an object in a fluid

• Magnetic force:

  • Force caused by moving charged particles

• Air resistance:

  • Force caused by air pushing on an object

• Weight:

  • Force between any two objects with mass

• Thrust:

  • Force pushing a vechicle

• Compression:

  • Force that squeezes an object

Scalar V.S. Vector

• Scalar: quantity with only magnitude

• Vector: quantity with magnitude and d