Solution :
Velocity of the car,
= 72 km/h
= 20 m/s
Distance from the intersection = 20 m
Velocity of the bicycle,
= 8 m/s
Distance from the intersection = 32 m
a). The time for the bicycle to reach at the center


The distance travelled by the car during text reading (3 s) =
x 3
= 20 x 3
= 60 m
Distance travelled by the car after braking and till the bike reaches at the center -- remaining time = 4 - 3
= 1 second
∴


= 17.5 m
So the total distance travelled by the car in 4 s = 60 + 17.5
= 77.5 m
So the distance between the car and the bike when the bike reaches at the intersection = 80 - 77.5
= 2.5 m
b). Speed of the car when the bike is at the intersection :
v = u - at
= 20 - (5 x 1)
= 15 m/s
= 15
m/s
= 8 cos 10
- 8 sin 10

Velocity of the car w.r.t cyclist,



c). When the car stops, the distance travelled by the car is

or


= 40 m
The car applied brake when it was 20 m before the intersection.
So the car will stop 20 m after the intersection.