A concave mirror is used in a solar furnace with the receiver kept at its principal focus
PHYSICS · Single correct · CBSE · Physics · Light: Mirrors and Lenses · Light: Mirrors and Lenses
Problem
A concave mirror is used in a solar furnace with the receiver kept at its principal focus. What is the main reason for this arrangement?
(a) The mirror converts parallel sunlight into parallel reflected rays that heat a wider area
(b) Placing the receiver at the principal focus makes the reflected rays strike it normally, so absorption is maximum
(c) The mirror concentrates parallel sunlight at the focus, raising the temperature greatly at that point
(d) At the principal focus the reflected ultraviolet rays are deflected away, keeping the receiver safe from harmful radiation