Question

(a). Write name of spherical mirror used as rear-view mirror in vehicles.
(b). An electric bulb is connected to a 220V generator. Write value of power of bulb if 0.5 A current is flowing through the bulb.

Answer 1

(a) Hint: A rear–view mirror is a flat-mirror in automobiles and other vehicles, designed to allow the driver to see rearward through the vehicle’s rear window.

Complete step-by-step solution:
In a car it is usually a plain mirror.
In motorcycles, side mirrors of cars & trucks/buses are usually a convex mirror to cover a wide area. That is the reason why you have a warning etched in the mirrors that the objects in the mirror are nearer than what they appear in the mirror.

Note:
In a car you can check your blind spot by looking over your shoulder, in a truck, bus or van this is sometimes impossible. The bigger the vehicle, the bigger the blind spot, which is why most big vehicles are equipped with convex mirrors.

(b) Hint:
Power tells us how much electricity the bulb can transform into light and heat over a given amount of time.

Complete step-by-step solution:
Given:
Voltage = V = 220V
Current = I = 0.5 A

Power law equation formula
We know that,

$Power{\text{ }} = {\text{ }}Voltage \times Current$
$P = V \times I$
$P = 220 \times 0.5$
$P = 110W$

Note:
$Power = I \times V = R \times {I^2} = \dfrac{{{V^2}}}{R}$
Where, P is power, I is current, V is voltage & R is resistance.