Ans
1
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relative velocity=(velocity 1 - velocity 2)...since velocity 2 is in opposite direction it carries a negative (-) sign with it.Thus vel.1-(-vel2)=vel.1 +vel.2...i hope that might be the answer for your querry....
8 years ago
by
sumit choudhary
Ans
2
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Try to learn physics by observing. When we are travelling in train and another train passes opposite to us it seems at a huge speed basically what happens let our speed be or rather velocity be V and that of other train be U and we know relative velocity of A with respect to B is VELOCITY OF A MINUS(-) VELOCITY OF B which in our case of train is V-U but concentrate on velocity direction both are in opposite direction so actually it V-(-U) which gives V+U hence ur answer.
Now think when we see a train moving parallel to our train in same direction it velocity seems to be much less and in case both have same velocity the it seems us to be at rest because V-U BECOME zero. Try to observe and learn
8 years ago
by
Gurpreet Singh