Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

In a Young's double slit experiment, the slits are 2 mm apart and are illuminated with a mixture of two wavelength   and λ = 900 nm. The minimum distance from the common central bright fringe on a screen 2m  from the slits where a bright fringe from one interference pattern coincides with a bright fringe from the other is

(a) 1.5 mm

(b) 3 mm

(c) 4.5 mm

(d) 6 mm

The e.m.f. of a cell is E volts and internal resistance is r ohm. The resistance in external circuit is also r ohm. The p.d. across the cell will be

(a) E/2

(b) 2E

(c) 4E

(d) E/4

The grid voltage of any triode valve is changed from –1 volt to – 3 volt and the mutual conductance is 3  mho. The change in plate circuit current will be

(a) 0.8 mA

(b) 0.6 mA

(c) 0.4 mA

(d) 1 mA

Magnitude of potential difference across L. C and R in a series LCR circuit is 100 V. If resistor is re- moved, then magnitude of current in the circuit is:

Crystal structure is studied by:

Current is flowing in a circular coil of radius r. There are n turns in the coil. Its magnetic moment varies with r. As:

Two lithium nuclei in a lithium vapour at room temperature do not combine to form a carbon nucleus because:

Two photons having _________________:

An electron and a proton are both released from rest 1 meter from a large stationary negative charge, considering only the force from the large stationary negative charge on the proton and electron. Which of the following is true?

Which device is used to produce electricity? Describe with a neat diagram.