A projectile is fired vertically upwards with an initial velocity u. After an interval of T seconds a second projectile is fired vertically upwards, also with initial velocity u.

(1) They meet at time t=ug and at a height u22g+gT28

(2) They meet at time t=ug+T2 and at a height u22g+gT28

(3) They meet at time t=ug+T2 and at a height u22ggT28

(4) They never meet

Concept Videos :-

#26-Equations-for-Uniform-Acceleration
#27-Equations for Uniform Acceleration 28Calculus Method29
#28-Sign Convention
#29-Solved Examples 16
#31-Solved-Examples-18
#32-Solved Examples 19
#33-Solved Examples 20
#34-Solved-Examples-21
#35 Solved Examples 22
#30-Solved Examples 17
#45-Relative motion
#46-Relative motion-1
#47-Relative motion-2
#48-Relative motion-3
#49-Relative motion-4
#50-Relative motion-5

Concept Questions :-

Uniformly accelerated motion
Relative motion in 1-D

(3) For first projectile, h1=ut12gt2

For second projectile, h2=u(tT)12g(tT)2

When both meet i.e. h1=h2

ut12gt2=u(tT)12g(tT)2

uT+12gT2=gtT

t=ug+T2

and h1=uug+T212gu2+T22

=u22ggT28

Difficulty Level:

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