Question

a car start from rest after 5 sec and accelerate uniformly for 10 sec before attaining a speed of 20 m/s. if it maintain this speed for the next 5 sec : draw a sketch graph to describe the journey ,use the sketch diagram to determine the uniform of acceleration. the total distance covered ,the average velocity.

Answer 1

The uniform of acceleration:

$$a=\frac{20-0}{10}=2\:\rm m/s^2$$

Total distance covered by the car is equal to area below the velocity curve:

$$d=\frac{5+15}{2}*20=200\:\rm m$$

The average speed:

$$v_{ave}=\frac{d}{t}=\frac{200}{20}=10\:\rm m/s$$