A concave mirror can be used to produce a parallel beam of light if a lighted bulb is placed
A
between its focus and the pole
B
at its focus
C
at its centre of curveture
D
between its focus and centre of curvature
Verified Correct Answer: B.
Physical Principles & Numerical Solution
When a light source is placed at the focus of a concave mirror, the rays of light that reflect off the mirror will emerge as a parallel beam of light.
This happens because when a point source of light is placed at the focal point of a concave mirror, the reflected rays leave the mirror parallel to each other.
Source: Myschool Past Questions Archive (Record #33820)