Why were there 50 answer boxes for the multiple choice?
There are other AQA subject exams that do multiple choice too and they use the same answer sheet. I'm guessing some of the subjects have 50 multiple choice questions
Q.20 is wrong, it would be 0, obviously the force is twice as great but the current is reversed to the force acts upwards thus the reading is zero, it asks for the reading not the relative force
Do you think it's worth writing a complaint to AQA about the obvious typo in the capacitors question? Just in case it hasn't come to their attention that their proof-reading process is awful...
Definitely not incorrect, I got it incorrect I said no damping. Change in Damping is not how to air resistance varies. It his how the air resistance varies in relation to change in momentum. If you don't believe me go and do an experiment, damping has no effect on time period in the first place.
The added mass doesn't effect damping. Of course damping affects the time period, but the mass added has not increased the damping force, as the time period is independent to the mass added, vmax is independent, and this equation here, the 'drag force' which is what the damping force in this instance is, is denoted below. It is true a damping force changes the time period, but changing the mass doesn't change the maximum velocity , assuming the ring has no significant area, which is a fair assumption.
Q.20 is wrong, it would be 0, obviously the force is twice as great but the current is reversed to the force acts upwards thus the reading is zero, it asks for the reading not the relative force
No, there has been a very similar question to this in a previous year (identical but with different numbers) and what they put for 20 is right
The added mass doesn't effect damping. Of course damping affects the time period, but the mass added has not increased the damping force, as the time period is independent to the mass added, vmax is independent, and this equation here, the 'drag force' which is what the damping force in this instance is, is denoted below. It is true a damping force changes the time period, but changing the mass doesn't change the maximum velocity , assuming the ring has no significant area, which is a fair assumption.
The first part of the question used a 150Ω resistor, and the second part a 300,000Ω resistor. This lead to a graph that could not be drawn accurately, as it had to start at 1/2000th of the height of the original line! Clearly they missed a 'kilo' off the 150Ω, or added one in on the 300kΩ