Questions Related to physics
Read the following statements and answer whether the given statement is true or false.
A transformer consists of two electrically isolated coils and operates on Faraday’s principle of mutual induction, in which an EMF is induced in the transformer secondary coil due to the magnetic flux generated by the voltages and currents flowing in the primary coil working. In self induction there is only one coil and emf is induced in that coil due to the change in flux linked with that coil.
A transformer works on both A.C. and D.C.
Transformer does not work on DC. Direct current doesn’t have a variable magnetic field induced if fed through the primary winding of a transformer. Thus, only a constant magnetic field will act on secondary and shall not induce any voltage across the terminals of the same.
Why are transformers used in the transmission of electric power?
Transformer used in the transmission of electrical power because they help to distribute electrical energy efficiently and can reduce transmission loss.
Which of the following statement about the action of a transformer is correct?
Alternating current does not flow in the secondary coil unless electrical load is connected to its terminals.
In step-up transformer current in secondary coil is less than the current in primary coil.
No e.m.f. is induced in the secondary coil if the primary coil is connected to a d.c. supply.
The current drawn by the primary of a transformer, which steps down 200 V to 20 V to operate a device of resistance 20 $\Omega$ is: (Assume the efficiency of the transformer to be 80 %)
In a step up transformer the turn ratio is 1:2. A Leclanche cell (emf = 1.5 V) is connected across the primary. The voltage across the secondary is
For the step up transformer -
A transformer works on the principle of
Transformer is used to
Transformer can be used on;
The magnetic resonance imaging is used as a tool of diagnosis to detect the injuries in human body. It is based on the principle that:
The basic principle of MRI is protons in different types of human tissues have specific magnetic field environment.