Teaching BPSC बिहार माध्यमिक TGT (9 to 10) शिक्षक भर्ती 4.0 Mock Test General Science Physics Optics
The focal length of a concave mirror with a radius of curvature of 30.0 cm is:
1
15 cm
2
20 cm
3
5 cm
4
More than one of the above
5
None of the above