Home
Class 11
PHYSICS
Two trains 121 m and 99 m in length are ...

Two trains 121 m and 99 m in length are running in opposite directions with velocities `40 km h^(-1)` and `32 km h^(-1)`. In what time they will completely cross each other?

A

9 s

B

11 s

C

13 s

D

15 s

Text Solution

Verified by Experts

The correct Answer is:
B
Here, `v_A = 40 km//h, v_B = - 32 ` km/h
Length of train A `l_A = 121 m `
Length of train B, `l_(B) = 99m `
Relative velocity of train A with respect to train B
`v_(AB) =v_(A) -v_B=40-(-32)=72km//h=72 xx5/18=20 m//s`
Total distance to be travelled by each train for completely crossing the other train = 121 + 99 = 220 m
`:.` Time taken each train to cross the other train `=220/20 =11s`
Hence , the two trains will cross each other in 11 s.
Promotional Banner

Topper's Solved these Questions

  • KINEMATICS

    MTG GUIDE|Exercise Topicwise Practice Questions (VECTORS)|23 Videos

  • KINEMATICS

    MTG GUIDE|Exercise Topicwise Practice Questions (SCALAR AND VECTOR PRODUCTS OF VECTORS )|16 Videos

  • KINEMATICS

    MTG GUIDE|Exercise Topicwise Practice Questions (KINEMATIC EQUATIONS FOR UNIFORMLY ACCELERATED MOTION|48 Videos

  • GRAVITATION

    MTG GUIDE|Exercise AIPMT/NEET MCQS|32 Videos

  • LAWS OF MOTION

    MTG GUIDE|Exercise AIPMT /NEET (MCQ)|24 Videos

Similar Questions

Explore conceptually related problems

Two trains 120 m and 80 m in length are running in opposite directions with velocities 42 km h^(-1) and 30 kmh^(-1) . In what time they will completely cross each other?

Two trains 120m and 100 m in length are tunning in opposite directions with velocityes 42 km h^(-1) and 30 km h^(-1) In what tiem they will completely cross each other ?

two trains A and B,each of length 100 m, in length are running in opposite driection on parallel tracks with velocities 40 kmh ^(-1) and 32 kmh^(-1) . In what time will they completely cross each other ?

Two trains 90 m and 120 in length are running in opposite directions on parallel tracks with velocitye 72 km//h and 36 km//h . In what tiem they will complerely cross each other ?

Two trains having lengths 120 m and 100 m running in the opposite directions with velocities 40 km/h and 50 km/h. In what time they will completely cross each other?

Two trains 110 m and 90 m log respectively, are trunning in opposite directions with velocities 36 km h^(-1) and 54 km h^(-1) Find the time taken by the trains to completely cross each other.

Two trains 132 m and 108 m long are running in opposite direction, one at the speed of 32 km/h and another at the speed of 40 km/h. In what time will they cross each other?

Two trains, each 50 m long, are travelling in opposite directions with velocities 10 ms^-1 and 15 ms^-1 . The time of their crossing each other is.

The length of Lucknow mail is 120 m and that of Punjab mail is 80 m. These two trains are running in the opposite direction with velocities of 40 km/h and 50 km/h respectively. The time taken by them to cross each other is :