Question:
A passenger sitting in a train A moving at 90 km/h
observes another train B moving in the opposite
direction for 8 s. If the velocity of the train B is
54 km/h, then length of train B is :
(1) 80 m
(2) 200 m 
(3) 120 m 
(4) 320 
                                                           JEE-2024   
Solution:                
A passenger sitting in a train A moving at 90 km/h observes another train B moving in the opposite direction for 8 s. If the velocity of the train B is 54 km/h, then length of train B is : (1) 80 m (2) 200 m (3) 120 m (4) 320 JEE-2024

Bhautik Study is a branch of knowledge that offers comprehensive solutions to a wide range of questions, aiding in preparation for exams such as JEE, NEET, CUET and NDA. 

The magnetic field at the centre of a wire loop formed by two semi circular wires of radii R1 = 2 πm and R2 = 4π m carrying current I = 4A as per figure  given below is  a × 10^–7 T. The value of a is  ______. (Centre O is common for all segments)           

                                                                      JEE-2024