A physics lab is designed to study the transfer of electrial energy from one circuit to another by means of a magnetic field using simple transformers. Each transformer has two coils of wire electrically insulated from each other but wound a round a common core of ferromagnetic material. The two wires are close together but do not touch each other
The primary `(1^(@))` coil is connected to a source of alternating `(AC)` current. The secondary `(2^(@))` coil is connected to resistor such as a light bulb. The `AC` source produces on oscillating voltage and current in the primary coil that produces an oscillating megnetic field in the core. material. This in turn induces an oscillating voltage and `AC` curent in the secondary coil
Students collected the following data comparing the number of turns per coil `(N)`, the voltage `(V)` and the current `(I)` in the coils of three transformers.
`|{:("Transformer","primary coil","Secondary coil"),(1,100 . 10V.10A,200.20V.5A),(2,100.10V.10A,50.5V.5A),(3,100.10V.10A,100.5V.20A):}|`

The primary coil of a transformer has 100 tunrs and is connected to a `120 V AC` source. How many turns are in the secondary coil if there is `2400 V` across it

Options

A. 5
B. 50
C. 200
D. 2000

Answer

D

Explanation

`(N_(1))/(V_(1)) = (N_(2))/(V_(2))` (we can from the table)
Hence `N_(2) = (N_(1))/(V_(1)) xx V_(2) = (100)/(120) xx 2400 = 2000`