HSC Science (Electronics) इयत्ता १२ वी - Maharashtra State Board Important Questions

1000 tiny mercury droplets coalesce to form a bigger drop. In this process, temperature of the drop _______ .

(A) increases

(B) may increase or decrease

(C) decreases

(D) does not change

If the total kinetic energy per unit volume of gas enclosed in a container is E, the pressure exerted by the gas is

(A) E

(B) 3/2 E

(C) `sqrt3E`

(D) 2/3E

Two gases exert pressure in the ratio 3: 2 and their densities are in the ratio 2: 3, then the ratio of their R.M.S. velocities is ...........

A body cools from 62°C to 54°C in 10 minutes and to 48°C in the next 10 minutes. Find the temperature of the surroundings.

The fraction of the total current passing through the galvanometer is ............ .

a) `S/(S+G)`

b) `G/(S+G)`

c) `(S+G)/G`

d) `(S+G)/S`

The susceptibility of magnesium at 300K is 1.2 x 10^-5. At what temperature will the susceptibility increase to 1.8 X 10^-5?

A moving coil galvanometer has a resistance of 25Ω and gives a full scale deflection for a current of 10mA. How will you convert it into a voltmeter having range 0 - 100 V?

Explain black body radiation spectrum in terms of wavelength

The substance which allows heat radiations to pass through is _______.

(A) iron

(B) water vapour

(C) wood

(D) dry air

A galvanometer has a resistance of 16Ω. It shows full scale deflection, when a current of 20 mA is passed through it. The only shunt resistance available is 0.06  which is not appropriate to convert a galvanometer into an ammeter. How much resistance should be connected in series with the coil of galvanometer, so that the range of ammeter is 8 A?

Four resistances 4Ω,8Ω,XΩ, and 6Ω are connected in a series so as to form Wheatstone’s
network. If the network is balanced, find the value of ‘X’.

The kinetic energy per molecule of a gs at temperature T is ________.

(a) `(3/2)RT`

(b) `(3/2)K_BT`

(c) `(2/3) RT`

(d) `(3/2)("RT"/M)`

A body cools from 80° C to 70° C in 5 minutes and to 62° C in the next 5 minutes. Calculate the temperature of the surroundings.

Explain with a neat circuit diagram how will you determine unknown resistance ‘X' by using meter bridge

Calculate the internal energy at 298K for the formation of one mole of ammonia, if the enthalpy change at constant pressure is – 42.0 kJ mol^-1.

(Given: R = 8.314 J K^-1 mol^-1)

The specific heat capacity of water is 

What is perfectly black body ? Explain Ferry’s black body.

Kirchhoff’s first law, i.e., ΣI = 0 at a junction, deals with the conservation of ______.

State any two sources of errors in the meter-bridge experiment. Explain how they can be minimized.

Choose the correct option.

The mean free path λ of molecules is given by where n is the number of molecules per unit volume and d is the diameter of the molecules.