Physics

Mechanics - Kinematics 2.1.1

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Instantaneous values of speed, velocity and acceleration is the value at a single moment in time, not over a period of time. Average values of all three are the average values of the speed/velocity/acceleration over a certain period of time, not just a single moment.
Average velocity is the difference between the beginning and the end.
e.g. distance = 16km, journey time = 4 hours
average velocity = 16/4
= 4 km h^-1
Average velocity = displacement/time
Average speed = distance/time
Average acceleration = change in velocity/change in time
unit of acceleration is m s^-2
Acceleration is a vector quantity

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The equations of uniformly accelerated motion can only be under conditions where the acceleration is constant.
SUVAT used for uniformly accelerated motion:
- v = u + at
- s = (u + v/2) t
- v^2 = u^2 + 2as
- s = ut + 1/2at^2
- s = vt - 1/2at^2

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Air resistance eventually affects all objects that are in motion. Due to the effect of air resistance objects can reach terminal velocity. This is a point by which the velocity remains constant and acceleration is zero.
In the absence of air resistance all objects have the same acceleration irrespective of its mass.

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Instantaneous velocity is how fast it’s going at that moment in time and in which direction.
Average velocity is the difference between the beginning and the end.
e.g. distance = 16km, journey time = 4 hours
average velocity = 16/4
= 4 km h^-1
average velocity = displacement/time
Instantaneous velocity = length/time for object to pass
Acceleration = change of velocity/time
unit of acceleration is m s^-2
Acceleration is a vector quantity

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