TPQN 3

JEE Mains Online › Mechanics questions › TPQN 3

Two particles of masses m1 and m2 in projectile motion have velocities v1 and v2 where velocities are vectors, at time t=0. They collide at time t, their velocities being v1' and v2' at time 2t. the value of modulus of (m1v1'+m2v2')-(m1v1+m2v2) is:
a)0
b)(m1+m2)gt
c)2(m1+m2)gt
d)(m1+m2)gt/2

#Physics #Mechanics

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8 Answers

1

skygirl ·2008-12-14 03:46:29

0.
no external force, momentum conserved.

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62

Lokesh Verma ·2008-12-14 04:01:20

no sky!

mg is acting for that time.

for time 2t.

force acting is (m1+m2)g

Does this hint suffice?!

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1

skygirl ·2008-12-14 04:08:43

oops sry. yeah..

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1

skygirl ·2008-12-14 04:09:55

then we can do it by
impulse= change in momenta..

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62

Lokesh Verma ·2008-12-14 04:10:44

but there is no impulse either ;)

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1

skygirl ·2008-12-14 04:14:15

no not impulse...

mÎ”v = 2(m1+m2)g ..

correct me if wrong agn :P

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1

~AjInKyA~ ·2008-12-14 04:42:55

mayb relative velocity b used !!
time is same for both . but r tey in opp or smae direction!!!!!!!?
is question komplet??

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6

Aakash Sharawat ·2008-12-14 16:25:45

absolutely nishant's hint is correct! the correct answer as per the answer key is C!!!!!!!!!!

thanks for the hint mentor!!!!!!!!!!

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