therefore it is pressing down on anything below it with:

A> 100% of its mass

B> 60% of its mass

C> 140% of its mass

D> 40% of its mass

An object is falling at a rate that is 60% of the acceleration of gravity

therefore it is pressing down on anything below it with:

A> 100% of its mass

B> 60% of its mass

C> 140% of its mass

D> 40% of its mass

therefore it is pressing down on anything below it with:

A> 100% of its mass

B> 60% of its mass

C> 140% of its mass

D> 40% of its mass

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If N is the force pressing down, then -N is the exterior force pressing it up.

Applying Newton's second law in vertical direction, with downward direction as positive,

mg - N = ma

N = mg-ma = mg - 0.6mg = 0.4 mg

Answer: D

Answer is D.

In the reference frame of an object there is an upward force, acting against the gravity and equal to 0.6 mg, where m is the mass of an object.

Therefore, the object is pushing on anything below it with mg-0.6 mg=0.4 mg force, which is equivalent to the 40% of its normal weight.

Unfortunately, I am not sure that some of the answers given here are correct! The confusion may be arising with the wording of the question If you look at the answer choices they are all expressed in terms of a percent of the mass of the object, not a percent of the weight of the object.

A distinction has to be made between the mass of the object, given by m, and its weight, which is mg. The weight of an object can be different under different conditions because this depends on g, however, the mass will remain the same unless it is being converted to energy (E = mc^2).

Therefore, in terms of the mass, I think the correct answer is A, i.e. 100% of its mass! Regardless of the upward forces experienced by an object, it will always press down on something below it with 100% of its mass.

Although I do agree with the two answers given, I wanted to give you some food for thought.

Technically the Earth is below the person falling. Even though you are not free falling, you are still pulling up on the Earth by your weight (mg).

Additionally, you are assuming there are only 2 forces acting on the falling person. That is, there is only the force due to gravity and an opposing force below the falling person (typically air resistance). However there could be more forces present and being applied by an object not necessarily below the person falling (ie a parachute).

Just some things to think about.

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