A convex lens of focal length 20 cm is used as a magnifying glass. For maximum magnification, object should be placed at MCQ with Answer and Explanation

Explanation:
Each cycle produces one compression. 256 cycles, 256 compressions.

Explanation:
Angle of incidence and reflection are measured with respect to the normal (perpendicular) at point of incidence. Not from surface. If angle from surface given, convert.

Explanation:
An ammeter must have very low resistance so it does not alter the circuit current it is measuring. To convert a sensitive galvanometer into an ammeter, a very low resistance called a 'shunt' is connected in parallel to it. This diverts most of the current away from the delicate galvanometer coil while still allowing a proportional measurement.