Question

Unit of reduction factor is:

• A. ampere
• B. ohm
• C. tesia
• D. weber

Answer 1

Answer: (A)

In a suspended coil galvanometer the strength of current is not proportional to the deflection $\text{o }|$ hence, cannot be read directly. To remove this difficulty the field is made radial. Hence, deflecting torque on the coil suspended in radial magnetic field is $NiAB$ where N is number of turns in coil, A is area of plane of coil and B is magnetic field. $NiAB=C$ $\varphi$
$\Rightarrow i=\frac{C}{NAB}\varphi \Rightarrow i=K\varphi$
where K is a constant called reduction factor. Its unit is same as of current that is ampere.