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General Thoughts: Physics (1 Viewer)

salcoo

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Did anyone happen to get 7700 m/s for the velocity of the satellite ?
 

IamKirby

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Did anyone happen to get 7700 m/s for the velocity of the satellite ?
Yeah I read someone did but I fucked it up BECAUSE I DIDNT READ THE UNITS. Sorry just pissed at myself because it was the easiest question in the exam.


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Drsoccerball

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did your line of best fit start from 0?
Yes it did because when the range is 0 the horizontal speed is 0.
Also we drew a line of best-fit for a reason, we have to use a point that lies on the line.
Also ill upload a sketch of what I did for the trolley/ cart question.
 

Drsoccerball

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It doesn't asymptote to zero but rather to a speed since there was no friction ( Since velocity never changed without the magnet).
 

apurba

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how come velocity doesn't increase again haha this is probs stupid as but I drew an increase in velocity after it leaves the magnet because i thought the direction of eddy currents would change & so the trolley would experience a force in the opposite direction, causing its velocity to gain slightly.

where did i go wrong haha
 

apurba

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It doesn't decrease through B and C

If you measure the trolley with the A-B-C-D range you'll find both are exactly 3cm

It should start decreasing slightly before since the magnet isn't situated exactly at point B

and since the magnet will continue attracting after the front of the copper has slid through (i.e. the back of the copper bar) it should begin increasing just before D
yeah this is what i did
 

PhysicsMaths

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I don't understand at all how velocity will increase. Where is the energy for the increase coming from?


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Nowhere. They have violated the law of conservation of energy / momentum.
 

Drsoccerball

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Shouldnt it have a horizontal point of inflexion somewhere, as when the copper plate is directly below the magnet, it experiences a constant flux, thus no change according to Lenz's law?
But theres still a change in flux ?
 

Drsoccerball

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At the point where its directly under? So like the same situation of when you have something moving within a field, and when its completely immersed, has no induced current.
Lets just say the magnetic field at 0.0001 meters away from the middle is X and right under is Y. Change in flux = X-Y and thus since they're not equal there has to be a change in flux? no?
 

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