The speed-time graph for a car is shown is Fig. 8.12.
(a) Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period.
(b) Which part of the graph represents uniform motion of the car?
The part of the graph between time 6s to 10s represents uniform motion of the car
In a velocity − time graph,
Distance = Area of v-t Graph
Here, we find approximate area using Area of Triangle
Distance = Area Δ OAB
= 1/2 × b × h
= 1/2 × 4 × 6
= 12 m
But, this is an inaccurate method to find Area, since the red portion is
∴ Total area = 15.2 + 0.8 + 0.4 + 0
= 16.4 sq units
Area under v − t graph gives distance
Hence, the distance covered by the car in 0−4 s = 16.4 m