Scenario A T = Mg M Scenario B T > Mg M Scenario C T = Mg M M Scenario D T < Mg M Scenario E T > Mg M Scenario F T < Mg m M Scenario G T > Mg M T > Mg m Scenario H T > Mg M Scenario I 2M T > Mg M Feedback Although your physical intuition may be sufficient to address many of the presented scenarios, a careful application of Newton's second law will always clarify the situation. Newton's second law states that the sum of the external forces sum vec{F}_{external} acting on a body will be equal to the body's mass M times its acceleration vec{a}. sum vec{F}_{external} = M vec{a} Consider the example of scenario A. There are only two external forces present: the tension vec{T} in the rope and the force of gravity, which is equal in magnitude to the object's mass times g. The former pulls upwards on the object, and the latter pulls downwards. Adopting up as positive, Newton's second law in the vertical, or y-direction, becomes T - Mg = Ma_{y}
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Identify the forces: In this scenario, the two forces acting on the body are the tension in the rope pulling upwards and the force of gravity pulling downwards. Show moreā¦
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