1. Acceleration
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2. What is acceleration?

3. Remember a change in direction also causes a change in velocity, so this is also acceleration.
Acceleration is also a vector, so it has a direction.
Negative acceleration is called deceleration.

4. a = (v – u) t acceleration = (final velocity – initial velocity)
time taken
a = (v – u) t
change in velocity
m/s
acceleration
m/s2
time s

5. Acceleration problem
A racing car accelerates from rest to a velocity of 60 m/s in a time of 4 seconds. What is the acceleration of the car?
change in velocity
time taken
acceleration = = 60 4
= 15 m/s2
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6. Acceleration problem
A hungry cheetah spots a gazelle and decides to chase it. The cheetah accelerates at 10 m/s2 from rest until it reaches 20 m/s. How long did this take?
acceleration =
change in velocity
time taken
time taken =
change in velocity
acceleration = 20 10
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= 2 s

7. Acceleration problems calculations

10. Questions