- #61
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That is the same as the general equation I obtained.Jpyhsics said:
Finding the acceleration of two masses on a pulley system
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The discussion focuses on calculating the acceleration of two masses connected by a pulley system, where one mass (m1) is on a surface and the other (m2) is suspended. The system is initially in equilibrium but will start sliding if m2's mass increases. Participants clarify that the coefficients of static and kinetic friction are equal, indicating friction is present. The horizontal acceleration of the surface is given as 5.43 m/s², but the horizontal acceleration of m2 is determined to be zero, as it does not directly respond to the surface's movement. The relationship between the accelerations of m1 and m2 is emphasized, with the conclusion that the string's constant length affects their acceleration dynamics.
- #62
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FriedChicken885
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haruspex said:
Okay, thank you very very very much for all of your help!
- #64
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Should one not consider that the tension supporting the hanging mass is no longer parallel to the vertical side of the table but at an angle?
Also, I think that ##g=9.81 ~m/s^2## in the expression posted by OP in #62 should be replaced by an effective acceleration. This problem can be solved quite simply in the accelerated frame with additional fictitious horizontal forces ##-m_i\vec a_0## acting on masses ##m_i##. Here, ##\vec a_0## is the given horizontal acceleration of the table.
Also, I think that ##g=9.81 ~m/s^2## in the expression posted by OP in #62 should be replaced by an effective acceleration. This problem can be solved quite simply in the accelerated frame with additional fictitious horizontal forces ##-m_i\vec a_0## acting on masses ##m_i##. Here, ##\vec a_0## is the given horizontal acceleration of the table.
- #65
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we are asked for the accelerations immediately after the surface has started to accelerate. The string is still vertical.kuruman said:
I don't see why. Do you get a different answer? If so, please post your solution.kuruman said:
- #66
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I don't get a different answer, but I am bothered by the fact that one writes the same equation for the hanging mass whether the pulley supporting it accelerates or not. When the pulley accelerates, the hanging mass must have a horizontal acceleration at t = 0 because its horizontal position changes a moment later. Should this not affect the tension? I need to think about this some more.
On Edit: OK, I got it. At t = 0 the horizontal acceleration is instantaneously zero and then changes as it reaches a constant value in the steady state.
On Edit: OK, I got it. At t = 0 the horizontal acceleration is instantaneously zero and then changes as it reaches a constant value in the steady state.
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- #67
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Right.kuruman said:
Or maybe oscillates.kuruman said:
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