Question

Please explain how to approach these problems

1)A 5-kg mass, call it S, moves with speed 10 m/s to the right. A second mass, 10-kg and call is T, moves to the left at 10 m/s. The masses collide head-on. The magnitude of the impulse on S by T to that on T by S is

1/4

1/2

1

2

4

None of these answers

2)A mass, S is 5-kg and moves to the right at 10 m/s. A mass T, is 10-kg and moves to the left at 10 m/s. The mass S is accelerating to the right at 2 m/s2 while the mass T is accelerating to the left at 1m/s2. The ration of the magnitude of the impulse on S by T to that on T by S is now

1/4

1/2

1

2

4

8

None of these answers

Answer 1

problem - 1

Given is :-

Now,

By applying conservation of momentum, we get

eq-1

and by conservation of kinetic energy we get

eq-2

from eq-1 and eq-2 we get

by plugging the values we get

which gives us

Similarly

by plugging all the values we get

which gives us

Now,

the impulse is given by change in momentum

therefore

change in momentum is s is

thus

which gives us

Similary the change in momentum for T is

by plugging all the values we get

hence

Now the impulse on S by T and on T by S will be same therefore

the answer is 1

Hence

option - 3 is correct answer.