The bending of light rays is the result of refraction of light passing through the lens. A converging lens is curved on both sides such that the rays coming out of it come together at a point (converge). The point at which the right rays meet after refraction is called the focal point which is a real in the convex lens.
Answer:

Explanation:
From the question we are told that:
Number of battery 
Voltage source
Lamp Power
Generally the equation for Resistance is mathematically given by



Therefore


Generally the equation for Current is mathematically given by



Energy can change form, but the total amount of energy stays the same.