Helping my daughter with her 7th grade physical science homework, we encountered a fairly straightforward word problem:
The calculations are straightforward.
a1 = 70/9.5 = ~7.4 m/sec2
a2 = 35/9.5 = ~3.7 m/sec2
Obviously the teacher is trying to illustrate that for a given force, acceleration increases as a product of mass.
That's where the question ends, right? When describing " the acceleration felt by each person" I would not subtract the opposing force of the child to describe the adult's acceleration as 3.7 m/s2 in one direction and the child's as the same in another. That's is, the " acceleration felt by each person" includes that part which is overcoming an opposite force?
A 70kg adult and a 35 kg child push against each other, each exerting 9.5N. Assuming no friction, describe the acceleration felt by each person.
The calculations are straightforward.
a1 = 70/9.5 = ~7.4 m/sec2
a2 = 35/9.5 = ~3.7 m/sec2
Obviously the teacher is trying to illustrate that for a given force, acceleration increases as a product of mass.
That's where the question ends, right? When describing " the acceleration felt by each person" I would not subtract the opposing force of the child to describe the adult's acceleration as 3.7 m/s2 in one direction and the child's as the same in another. That's is, the " acceleration felt by each person" includes that part which is overcoming an opposite force?
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