Adevice that changes mechanical energy to electrical energy by rotating a coil of wire through a magnetic field is called a(an)
a. transformer.
b. generator.
c. electromagnet.
d. current meter.

The correct answer to the question is : B) Generator.

EXPLANATION:

As per the question, the mechanical energy is converted into electrical energy.

All the power plants like thermal power plant, nuclear power plant and hydroelectric power plant use the same concept to produce electric energy.

Let us consider hydro power plant.

In hydro power plant, the water falling with high speed is allowed to fall on a turbine. The kinetic energy of the water rotates the turbine. The turbine is attached to a generator.

The coil of wire attached to it is rotated through a magnetic field and electricity is produced due to electromagnetic induction.

Hence, the correct answer to the question is generator which converts mechanical energy into electrical energy.

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray