Question

Two particles, each of mass m, are initially at rest very far apart.

Obtain an expression for their relative speed of approach at any instant as a function of their separation distance d if the only interaction is their gravitational attraction to each other.
Express your answer in terms of some or all of the variables m, d, and gravitational constant G.

I got sqrt(Gm/d) but it says I have an "incorrect numerical multiplier", which I think means something went wrong algebraically?

Answer 1

YOU ARE RIGHT!

you got the correct expression for velocity of EACH particle.

however the question asks the RELATIVE velocity

well done!

relative velocity or

$\text{ velocity of particle a with respect to particle b }\\ \vec v_{ab}= \vec v_a -\vec v_b$

remember this is velocity (direction and magnitude) kt Speed

Answer 2

Answer:we can calculate the expression by usingformula of gravitational force.

Explanation: