Verified Solution • 2025–26 Session
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QAIPMT-2005-Ph-2549: NEET 2005 Physics - Class 11 AIPMT-2005-Ph-2549 Solution: Two boys are standing at the ends A and B of a ground where AB…
Two boys are standing at the ends A and B of a ground where AB = a. The boy at B starts running in a direction perpendicular to AB with velocity . The boy at A starts running simultaneously with velocity v and catches the other in a time t, where t is
Multiple Choice Options
- A
- B
- C
- D
Step-by-Step Verified Solution
Velocity of A relative to B is given by
v A / B _ = v A _ _ v B _ = v _ _ v 1 _ ...(i)
By taking x-components of equation (i), we get
0 = v sin _ _ _ v 1 _ sin _ _ = v 1 v ...(ii)
By taking Y-components of equation (i), we get
v y = v cos _ _ ...(iii)
Time taken by boy at A to catch the boy at B is
given by
t = Relative d i s p l a c e m e n t a l o n g Y _ a x i s Relative v e l o c i t y a l o n g Y _ a x i s
= a v cos _ _ = a v . 1 _ sin 2 _ = a v . 1 _ ( v 1 v ) 2
[From equation (i)]
= a v . v 2 _ v 1 2 v 2 = a v 2 _ v 1 2
= a 2 v 2 _ v 1 2