<u>Answer</u>:
Step Down Transformer: The Transformer that expands the voltage from Primary (essential) to Secondary (auxiliary) (more optional twisting turns than essential winding turns) loops called Step Down Transformer.
<u>Explanation</u>:
A transformer that reduces high voltage to low voltage is called a step-down transformer. The step-down transformers are that transformers which have high turns on its primary coils than secondary.
Where
Vp = Voltage in Primary Coil
Ip = Current in Primary Coil
Vs = Voltage in Secondary Coil
Is = Current in Secondary Coil
According to John Dalton, atoms are indivisible which means that they can not be broken down into smaller particles. However, J.J Thomson have proven the existence of electrons. The existence of sub-atomic particles disproved Dalton's theory. Thomson conducted his experiment using a cathode ray-tube.
Answer
Correct Answer is D ( so that there will be a change in the magnetic field required for induction)
Explanation:
Transformer is a device in which electrical energy is transferred between two or more circuits.
Transformer working is based on Faraday’s law of electromagnetic induction. Transformation action in a transformer occur due to mutual induction between two or more winding.
A transformer consists of one or more winding which are coupled magnetically and separated electrically with a magnetic core. A changing or varying current in one coil of the transformer produces a changing magnetic flux due to which an emf (electromotive force ) is induced across the second coil which is wound around the same core.
Therefore a transformer needs an AC due to which a changing magnetic field will be created and due to this changing magnetic field an emf will induced in the second coil.
If DC is used in transformer then magnetic induction will not takes place since DC current will remain constant
Density is mass over volume: d=m/v
d = 393/50 => d = 7.86 g/ml
