1. In an electromagnet, adjusting the variable resistor alters the size of the current. Explain the effect on the strength of the electromagnet.
Increasing the resistance of the variable resistance will decrease the current flowing through the wire which will decrease the size of the magnetic strength of the electromagnet.
What other methods are there to increase the strength of the electromagnet.
Increasing the number of turns in the coil.
Inserting a soft iron core.
2. *State the function of the split-ring commutator in a d.c. motor.
The purpose of the split-ring commutator is to reverse the direction of the current in the coil every half a revolution to ensure that the coil will always rotate in one direction.
— Adelle Wang, River Valley High School
CF probably has the best Physics tutors in Singapore. They are able to explain difficult concepts clearly, as they provide short cuts and teach much easier methods of comprehending theory. Tuition is usually seen as a tedious and tiring activity but I always feel like their lessons pass very quickly as it is well-paced, suited to his students needs, and interesting at the same time. My Physics grades have improved from an S during mid-years to a B during prelims under their tutorship.
— Liew Yee Kay, Anglican High School
I always had much difficulty with Physics and found it a cumbersome and boring subject. But after attending Concept First Physics tuition class, I slowly understood it and finally got an A1 at the end! One thing I really appreciate about my tutors at CF is the fact that they cared for us all as individuals. When I was unsure about other subjects like A. Math, my tutors would stay back after class with me to clear my doubts. And for that, I’m really thankful!