Chapter 9.2 Acceleration

Question 1

Acceleration:

Answer 1

Rate at which an object changes its velocity (a speed and direction).

Question 2

Terminal velocity:

Answer 2

The constant speed that a free falling object eventually reaches when the resistance of the medium (i.e. air resistance) through which it is falling prevents further acceleration.

object isn’t accelerating nor declerating (velocity remains contant)

Question 3

Average Acceleration Formula

Answer 3

a=(v-u)/t

Question 4

Finding Final speed Formula

Answer 4

v= (at)+u

Question 4

1) A car speeds up to 56km/h from rest in 7 seconds. Calculate its average acceleration. Answer in km/h/s.

Answer 4

8km/h/s

Question 5

2) Teddy is jogging at a speed of 2m/s. He accelerates at the rate of 2m/s/s for 4seconds. What is his final speed (in m/s)?

Answer 5

10m/s

Question 5

3) A train initially travelling at 18km/h accelerates at a constant rate of 2m/s/s for 10 seconds.
Calculate its final speed in km/h.

Answer 5

90 km/h

Question 6

4) A remote controlled car speeds up to 9km/h from rest in 6 seconds. Calculate its averageacceleration (in km/h/s).

Answer 6

1.5 km/h/s

Question 7

5) A helicopter initially travelling at 36km/h accelerates at a constant rate of 3m/s/s for 15 seconds.
Calculate its final speed in km/h.

Answer 7

198 km/h