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A man pushes horizontally on a block at rest. Which of the following is true?
A. Newton's 3rd Law dictates that the block experiences a force equal and opposite to the pushing force.
B. Newton's 1st Law dictates that in the absence of any other forces, the block will remain at rest.
C. Regardless of other forces that may be acting on the block, the acceleration of the block will be inversely proportional to its mass.
D. Newton's 3rd Law dictates that an equal and opposite force will cancel the pushing force and the block will not move.
Correct answer is C.
I ruled out C off the bat, because to me, "inversely proportional" designates that there is a constant present. So, either the Force would have to be constant, which it is not ("Regardless of other forces"). After all, when a is inversely proportional to b, if you multiply a by 5, then b is multiplied by the reciprocal (1/5). Thus, I marked B, because I assumed that perhaps the man's force had not overcome static friction. C simply did not make sense!
So, my question is: is my definition of "inversely proportional" incorrect for physics? Is there an assumption that I'm not seeing here? If the "Regardless of other forces" were not there, I would most likely have marked C, because the force would be constant. Or, if the answer had been phrased "Regardless of other forces, the acceleration of the block will be directly proportional to the Force" because mass, unlike force, is reasonable to assume as a constant.
I know it seems like I am over thinking this, but when answering the question, I didn't overthink it. I just ruled C out because the force could not be taken as a constant!! How can I avoid doing that on the MCAT? I find the wording to be really ambiguous in much of the physical sciences.
A. Newton's 3rd Law dictates that the block experiences a force equal and opposite to the pushing force.
B. Newton's 1st Law dictates that in the absence of any other forces, the block will remain at rest.
C. Regardless of other forces that may be acting on the block, the acceleration of the block will be inversely proportional to its mass.
D. Newton's 3rd Law dictates that an equal and opposite force will cancel the pushing force and the block will not move.
Correct answer is C.
I ruled out C off the bat, because to me, "inversely proportional" designates that there is a constant present. So, either the Force would have to be constant, which it is not ("Regardless of other forces"). After all, when a is inversely proportional to b, if you multiply a by 5, then b is multiplied by the reciprocal (1/5). Thus, I marked B, because I assumed that perhaps the man's force had not overcome static friction. C simply did not make sense!
So, my question is: is my definition of "inversely proportional" incorrect for physics? Is there an assumption that I'm not seeing here? If the "Regardless of other forces" were not there, I would most likely have marked C, because the force would be constant. Or, if the answer had been phrased "Regardless of other forces, the acceleration of the block will be directly proportional to the Force" because mass, unlike force, is reasonable to assume as a constant.
I know it seems like I am over thinking this, but when answering the question, I didn't overthink it. I just ruled C out because the force could not be taken as a constant!! How can I avoid doing that on the MCAT? I find the wording to be really ambiguous in much of the physical sciences.