A ball of mass 2 kg is placed at position A at a height of 50 m from the ground. The initial velocity is 0 m/s. If the ball starts rolling down an inclined plane, what are the potential and kinetic energies at positions A, B, C and D in Joules assuming that the ball does not experience any frictional force (total mechanical energy does not change)

c, 1a hope this

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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r = ρ x length / area  

ρ = r x area / length  

ρ is in ohm-meters  

in basic units, it is m³kg/s³a²  

i think this is it.