A spherical convex surface of radius of curvature 20 cm, made of glass (μ = 1.5) is placed in air. Find the position of the image formed, if a point object is placed at 30 cm in front of the convex surface on the principal axis.

(a) An alternating voltage E = E_o sinωt is applied to a circuit containing a resistor R connected in series with a black box. The current in the circuit is found to be I = I_o sin (ωt + π/4).

(i) State whether the element in the black box is a capacitor or inductor.

(ii) Draw the corresponding phasor diagram and find the impedance in terms of R.

The magnetic field in a plane electromagnetic wave is given by:

B_y = 12 × 10^–8 sin (1.20 × 10⁷ z + 3.60 × 10¹⁵ t) T. Calculate the

(i) Energy density associated with the Electromagnetic wave

(ii) Speed of the wave

Name the optoelectronic device used for detecting optical signals and mention the biasing in which it is operated. Draw its I- V characteristics.

Give reason, why high frequency carrier waves are needed for effective transmission of information signals.

OR

What is the range of frequencies used for T.V. transmission? State two factors by which the range of TV signals can be increased.