Question (1 Viewer)

Run hard@thehsc · May 4, 2022

So in a generator, is there a relationship between anticlockwise torque and clockwise torque on the direction of emf (considering the field lines and direction are unchanged)? Asking this cos I got a flipped graph even after accounting for the negative in the emf in the following question....

(I got a graph going downwards first lmao)

Lith_30 · May 4, 2022

Idk if this would even work but...

Using Faraday's law $\epsilon=-N\frac{{d}\phi}{dt}$

using chain rule $\frac{{d}\phi}{dt}=\frac{{d}\phi}{d\theta}\times\frac{{d}\theta}{dt}$

using the magnetic flux equation $\phi=BA\cos(\theta)$
$\frac{{d}\phi}{d\theta}=-BA\sin(\theta)$

therefore $\frac{{d}\phi}{dt}=-BA\sin(\theta)\times\omega$ cause $\frac{{d}\theta}{dt}$ is just angular velocity

Hence $\epsilon=N{\omega}BA\sin(\theta)$

Thus I can sub the torque equation $\tau=nABI\sin(\theta)$

To get $\epsilon=\frac{\omega\tau}{I}$

So I guess that it depends on how we define what direction positive torque is defined as, which in this case is anti-clockwise I guess :/

Question (1 Viewer)

Run hard@thehsc

Well-Known Member

Attachments

Lith_30

o_o

Users Who Are Viewing This Thread (Users: 0, Guests: 1)