Forces & Motion: Facts You Should Know!!

SPM Physics :FAST Facts You Should Know About Chapter 2 Form 4!!
Compiled by cikgufizik @ www.physics4spm.com

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FAST Facts about Speed & Velocity

1. Speed, distance [d], time, and energy (joules) are scalar quantities.
2. Speed is rate of change of distance, i.e = distance/time
3. The gradient of distance-time graph is a speed.
4. Velocity, displacement [s], momentum, force and acceleration are vectors.
5. Velocity is the rate of change of displacement, i.e = displacement / time
6. The gradient of the displacement-time graph is also the velocity.

FAST Facts about Forces & Acceleration

1. Acceleration is the rate of change of velocity.
2. The gradient of the velocity-time graph is also the acceleration.
3. Zero acceleration also means either the object is at rest or moving at constant velocity.
4. Weight (in newtons) is mass x gravitational acceleration (w = mg). Mass is not weight!
5. Unbalanced forces will produce acceleration, i.e object not in equilibrium
6. Constant velocity and zero velocity means the net force is zero and the forces are in equilibrium
7. The equilibrium forces is equal in magnitude but opposite in direction to the resultant vector.

FAST Facts about Momentum

1. Momentum is a product of mass & velocity.
2. Momentum is conserved in all collision systems.
3. Total momentum before collision = total momentum after collision
4. Rate of change of momentum over time is an impulsive force. ( mv-mu) /t
5. Change in momentum is an impulse (mv-mu)

FAST Facts about POWER & ENERGY

1. Energy is a work done.
2. Energy is a scalar qty.
3. Energy can't be created or destroyed by human.
4. Energy can only be transformed.
5. Total energy dring the transformation is constant. (Total initial energy = Total final energy)
6. Gravitational potential energy increases as height increases.
7. Kinetic energy changes only if velocity changes.
8. Eleastic potential energy of the spring increases as the extension or compression of the spring increase.
9. The units for power are [joules/sec] or Watt (W).
10. Power is the rate of work done
11. 1 watt is 1 joule of work being done in 1 second.