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How could I calculate the internal resistance of a cell?

Firstly, we must set-up an experiment and would need the following apparatus: The cell, a voltmeter, an ammeter and a variable resistor (a rheostat for this example). Setup the experiment so that the cell...

Answered by Aman J. • Physics tutor

7108 Views

Define the moment of a couple

The moment of a couple is the force times the perpendicular distance between the lines of action of the force.

Answered by Heather W. • Physics tutor

3480 Views

An object with weight w is suspended from two strings at angles θ1 and θ2 to the vertical and with tensions T1 and T2. How would you resolve the vertical and horizontal forces?

Horizontal: T1 sin θ1 = T2 sin θ2Vertical: T1 cos θ1 + T2 cos θ2 = w

Answered by Heather W. • Physics tutor

2963 Views

If a wire loop moves at constant speed into a region where there is a magnetic field, why is a current induced in the wire?

In this question, a square wire loop of length L and resistance R starts in a region with no magnetic field, and moves at a speed v into a region with magnetic field B, which is acting perpendicular to th...

Answered by Gus B. • Physics tutor

1905 Views

From what height, h, should a rail-cart fall to complete a loop-the-loop of radius r without falling off a the track? Assume the track on which the rail-cart travels is smooth and express h in terms of r.

This question combines the principles of energy conservation and circular motion. The insight is to realise the condition for which the rail-cart will fall off of the track - when there is no contact forc...

Answered by Benjamin R. • Physics tutor

1109 Views