How to calculate the time over which flux changes

  • Thread starter Thread starter poortech
  • Start date Start date
  • Tags Tags
    Flux Time
AI Thread Summary
To calculate the time over which magnetic flux changes in a 50-turn coil, the formula E = -N (change in flux / change in time) is used. Given a change in flux from 10 mWB to 20 mWB and an induced e.m.f. of 62.5 V, the calculation leads to a negative time value, which is not physically meaningful. The negative sign can be disregarded since e.m.f. is typically expressed as an absolute value. The calculated time for the flux change is 0.008 seconds. Understanding the polarity of e.m.f. is crucial for accurate calculations.
poortech
Messages
8
Reaction score
0
1. if the magnetic flux linking all the turns of a 50 turn coil changes from 10 mWB to 20 mWB and induces an e.m.f. of 62.5 V in the coil, calculate the time over which the flux changes.

i know the formula to calculate the flux which is

E = -N change in flux / change in time.

to calculate the change in time we just need to change E with change in time in the formula, but by doing this answer will be negative which is not possible as time can not be negative. how to get rid of this -ve. or is it ok if i don't use it at all.


my answer is -0.008 Sec.



Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org
The 62.5V polarity was not defined with respect to coil geometry so your answer is correct when made positive.
 
62.5 V is an absolute value of e.m.f
 
thnx a lot guyz... :D
 
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Correct statement about a reservoir with an outlet pipe'
The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
Back
Top