Home
Class 11
PHYSICS
A police is chasing a culprit going n a ...

A police is chasing a culprit going n a motorbike. The motorbike crosses a turning at a speed of 72 km/h.
The jeep follows it at a speed of 90 km/h, crossing the turning tenseconds latert than the bike. Assuming that they tavel at constant speeds, how far from the turning will the jeep catch up with the bike?

Text Solution

Verified by Experts

The correct Answer is:
A, B, C, D
`V_p=0` km/h=25 m/s
`V_e`= 72 km/h=20 m/s
In 10 sec culprit reaches at point B from A. Distance covered by culprit
`S=vt=20xx10=200m` At time t=10 sec
the police jeepis 200 m behind the Culprit.
Relative velocity between jeep and culprit
`25-20`=`5m/s`
Time =S/v= 200/5=40s (Relative velocity is considered).`
In 40 s the police jeep will move from A to a distance S
where `
S=vt=25xx40
= 1000 m = 1.0 km` away
`:.` The jeep will catch up with the bike, 1 km far from the turning.
Promotional Banner

Similar Questions

Explore conceptually related problems

A man can swim with a speed of 4.0 km/h in still water . How long does he take to cross a river 1.0 km wide if the river flows steadily at 3.0 km/h and he makes his strokes normal to the river current ? How far down the river does he go when he reaches the other bank ?

A cyclist is riding with a speed of 27 km /h . As he approaches a circular turn on the road of radius 80 m , he applies brakes and reduces his speed at the constant rate of 0.50m//s every second . What is the magnitude and direction of the net acceleration of the cyclist on the circular turn ?

A motor car moving at a speed of 72 km/h cannot come to a stop in less than 3.0 s while for a truck this time interval is 5.0 s. On a highway, the car is behind the truck both moving at 72 km/h. The truck gives a signal that it is going to stop at emergency. At what distance the car should be from the truck so that it does not bump onto (collide with) the truck. Human response time is 0.5 s.

A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km h^(-1). Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km h^(-1). What is the (a) magnitude of average velocity, and (b) average speed of the man over the interval of time (i) 0 to 30 min, (ii) 0 to 50 min, (iii) 0 to 40 min ? [Note: You will appreciate from this exercise why it is better to define average speed as total path length divided by time, and not as magnitude of average velocity. You would not like to tell the tired man on his return home that his average speed was zero !]