An object has a mass of 120 kg on the moon. What is the force of gravity acting on the object on the moon?
A. 12.24 N
B. 20 N
C. 1,176 N
D. 196 N User: A man standing on a bus remains still when the bus is at rest. When the bus moves forward and then slows down the man continues moving forward at the original speed. This is an example of the effect of
A. velocity.
B. gravity.
C. weight.
D. inertia.

Respuesta :

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.
AL2006

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.