Question

Two spherical bodies of mass M and 5M & radii R and 2R respectively are released in free space with initial separation between their centres equal to 12R.

If they attract each other due to gravitational force only then the distance covered by the smaller body just before collision is :-

(a) 2.5R

(b) 4.5R

(c) 7.5R

(d) 1.5R


✔️✔️Proper solution Needed✔️​✔️​

Answer 1

ANSWER

c)7.5 R

Step By Step Explanation

Plz refer to the attachment given above for the diagram.

Now,

Here the net force is zero and also the displacement will also be zero.

So we have >

$m_{1}\delta x_{1} + m_{2}\delta x_{2} = 0$

$(M)_{1}\delta x_{1} - 5m_{2}\delta x_{2} = 0$

$\delta x_{1} - 5\delta x_{2} = 0$ ---------------(i)

and also,

$\delta x_{1} + \delta x_{2} = 9R$

---------------(ii)

$\delta x_{1} - 5\delta x_{2} = 0$

-------------------(iii)

Now multiplying by 5 on both sides if equation (ii) we get

=> $5 \delta x_{1} + 5 \delta x_{2} = 45R$ ----------(iv)

Adding equation (iii) and (iv) we get

=> $6\delta x_{1} = 45R$

=>$\delta x_{1} = \dfrac{45R}{6}$

=>$\delta x_{1} = \dfrac{15R}{2}$

=> $\delta x_{1} = 7.5R$

Hence the distance covered by the smaller body just before the Collison will be 7.5 R.

So your answer is option number {C}.

Answer 2

Hello Friend..❤️❤️

The answer of u r question is..✌️✌️

Option.C

For more information refer to the attachment!!

Thank you..☺️☺️