Question

An object has a mass of 120 kg on the moon. What is the force of gravity acting on the object on the moon?

Answer 1

For first question, Gravity is approximately up to 1/6 of Earth's gravity. So object's weight 1200/6=200 N. So answer shall be D.

For second question, intertia is the thing that described in the question. Answer is D.

Answer 2

Well first of all, if the object's mass is 120 kg, then its mass is 120 kg. 
It makes no difference where it happens to be located at the moment. 
Its mass is 120 kg. Period.  It doesn't change.

Weight = (mass) x (acceleration of gravity) .

Acceleration of gravity on the moon is 1.622 m/s² (rounded) .

Weight of the object = (120 kg) x (1.622 m/s²) = 194.6 Newtons.
                                                                   (about 43.8 pounds)

The nearest choice is  D). 196 N.

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When the bus starts moving forward, the man remains still. 
He leans back, and soon catches up.

When the bus is moving but begins to slow down, the man
continues moving forward at the same speed.  He leans forward,
until the bus stops, and then he eventually stops.

The simplest way to explain this (although it doesn't tell you much)
is to invoke 'inertia'.  'D' is the choice of the choices.