<p>Q75 was 2 masses hanging on a pulley. One of them was bigger in size and more down, the other one was smaller in size and a little higher.
Can’t remember exactly but I think I answered that with the logic of a child as well @ccusuer, haha :P</p>
<p>no… i think the answer for the 2 block hanging in the pulley is that they had the same mass… if one has bigger mass, the system would not be stable, it would fall to one side…</p>
<p>T-T come on what was question 70?</p>
<p>for the 2 pulleys, the system was stable and mass m was higher up than mass M (capital). </p>
<p>I don’t remember the options but I think I said mass m was heavier since it was higher up while being balanced. If it was higher up and they had the same mass I think the system would be in motion.
I’m not sure though.</p>
<p>I thought for the mass one they’d have the same mass because they were stationary so mg was the same for both of them. Idk though</p>
<p>Honestly I answered the question intuitively. </p>
<p>I know from experience if you put two object of equal mass on a pulley at the same height, they will be stationary. But if you move one further up and let go, they will start moving. So my reasoning that it could only be stable if the one further up had a larger mass. </p>
<p>again, i’m not 100% sure</p>
<p>If the one further up had a larger mass, It will never be stationary unless there are external forces… The system will keep moving even on the equilibrium height…</p>
<p>@poster
In real life that is true because the rope/string has a mass however in this problem the rope/string is assumed to have no mass. The 2 blocks are equal in mass</p>
<p>Does anyone remember what questions 70-75 were on the test? I can’t seem to recall the last few questions except for the open switch question and the mass+pulley question</p>
<p>I chose that one had a bigger mass… But now I think it was the wrong option. :(</p>
<p>One had a bigger mass, but by very small amount.</p>
<p>The rope is frictionless, so this is all theoretical.</p>
<p>Gravity is dependent on radius, so the one higher would have to be heavier to counter the increase in radius.</p>
<p>no… gravity is not dependent on radius of the thing…</p>
<p>I think that what you mean is the radius of the earth, which is essentially the space between the center of the earth and the center of the thing…</p>
<p>Lol, the r in Newton’s equation is not a radius but the distance between their centers of mass.</p>
<p>You do realize what the center of the mass of the earth is right?</p>
<p>Hi I might be off topic but I still did not have an answer. Do you guys know where I can find past SAT physics tests. I scored 700 last year and really want to have a 800 on the January test. Can anyone help me ?</p>
<p>When do scores come out?</p>
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<li>Omitted 11 and missed a ton more but… Overall, satisfied. I haven’t taken any second semester physics so I didn’t know about a quarter of the test beyond midnight cramming.</li>
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