The mass of the child in this problem is 24 Kg, the unit for mass is in Kilogram.
The mass will change only if it travels close to the speed of light.
I’d think the answer would be C. i’m just kinda guessing but my thought process is this (as simply as i can put it because physics is confusing):
so for example say you throw a ball across a flat surface. inertia is what keeps the ball rolling straight in a line, so unless you were to maybe put your hand in front of the ball or something, it would just go straight forever.
this is what happens with the planets. they go in a straight line, but since there’s gravity, the planets are also being pulled towards the sun. so gravity and inertia are why the planets orbit in the circle pattern they do. so when we remove inertia, we’re removing the state in which the planets keep going straight while being pulled towards a center point (the sun). this causes gravity to be the only factor in the planets orbiting. so that being said, the planets would just be pulled towards the sun. :)
Final speed = initial speed + (acceleration x time)
(final speed - initial speed) = acceleration x time
Time = (final speed - initial speed) / acceleration
The answer is a.12.5kg because i just did the test and it was correct.
hope this helps
