I found this on arxsiv.org: “The central force motion between two bodies about their center of mass can be reduced to an equivalent one body problem in terms of their reduced mass m and their relative radial distance r. ... The potential V (r) from which this force is derived is also a function of r alone, F = −VV, V ≡ V (r).”
Mark as BRAINLIEST?
Their relative speed is the sum of 60 and 40 or 100km/hr. They will travel the 150km in 1.5 hrs. When two object approach each other, the closing speed is just the sum of the speeds, therefore, the closing speed is your case is 100kph. So they will meet in 1.5 hours.
Mechanical energy = potential energy + kinetic energy
The ball is on the ground so it has no potential energy. that's all i know.