Help with designing an investigation

AI Thread Summary
The discussion revolves around designing an investigation into transformers using specific equipment, including a signal generator and oscilloscope. The signal generator is intended to provide the primary emf, allowing for frequency variations to observe transformer behavior, while the oscilloscope is used to visualize waveform changes in the secondary output. Participants suggest testing different frequencies, particularly in the 10-50Hz range, to assess the transformer's response. The loudspeaker can serve as an audio indicator of frequency response, confirming when the signal attenuates. Overall, the investigation aims to explore the relationship between frequency and transformer efficiency while utilizing all provided equipment effectively.
Jimmy87
Messages
692
Reaction score
19

Homework Statement


We have been asked to design an investigation into transformers. The equipment list given is: coils of wire, iron core, ammeter, voltmeter, loudspeaker, signal generator and an oscilloscope.

Homework Equations

The Attempt at a Solution


I know that you could investigate how changing the number of turns on the primary affects the secondary emf. However, we were asked to try and use all the equipment. What is the point of using a signal generator? Looking online it seems to say to stick to around 50Hz and nothing I have found seems to suggest changing the frequency of the primary current? Could this be done? What could I use the oscilloscope for?

Thanks for any help offered.
 
Physics news on Phys.org
Jimmy87 said:
I know that you could investigate how changing the number of turns on the primary affects the secondary emf.

That's correct but only if there is a primary emf. Check your equipment list again. What could you use to generate the primary emf?
 
  • Like
Likes Jimmy87
CWatters said:
That's correct but only if there is a primary emf. Check your equipment list again. What could you use to generate the primary emf?

Thanks. Ok, so the signal generator would provide the emf? Why use a signal generator and not a power pack then?

What would you use the oscillioscope for if you already have a voltmeter to measure the secondary emf? Also have no idea about the loudspeaker?
 
Jimmy87 said:
Thanks. Ok, so the signal generator would provide the emf? Why use a signal generator and not a power pack then?

You could use an AC power supply if you have one (It would be too dangerous to use the AC mains directly).

Jimmy87 said:
What would you use the oscillioscope for if you already have a voltmeter to measure the secondary emf?

I agree there could be some redundancy. Can your voltmeter measure AC or just DC? Has the oscilloscope got two inputs?

Also have no idea about the loudspeaker?

50Hz is just about in the audible range.
 
  • Like
Likes Jimmy87
I suspect the idea of the signal generator and oscilloscope is for you to do a frequency sweep of your coil circuit (with sig. gen.) and show the frequency response on the oscilloscope. You can also use the speaker to provide an audio confirmation that the signal starts to attenuate around the particular frequency that you predicted. (I am assuming that the signal generator operates in the audio range.)
 
  • Like
Likes Jimmy87
CWatters said:
You could use an AC power supply if you have one (It would be too dangerous to use the AC mains directly).
I agree there could be some redundancy. Can your voltmeter measure AC or just DC? Has the oscilloscope got two inputs?
50Hz is just about in the audible range.

Thanks. It says in my guidance to use the signal generator to observe the operation of the transformer at different frequencies. So in terms of independent, dependent and control variables could I do the following:

Change the frequency of the primary current (independent variable)
Measure the voltage or oscilloscope reading on the secondary (dependent)
Keep the number of turns the same (control)

Would this work? What would be a suitable frequency range to test? 10-50Hz in steps of 10?

I found out from someone else that the oscilloscope is mainly for us to see that the waveform on the secondary is unchanged whatever that means?
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top