HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions

Show that the surface tension of a liquid is numerically equal to the surface energy per unit
area.

In Melde’s experiment, the number of loops on a string changes from 7 to 5 by the addition of 0.015 kgwt. Find the initial tension applied to the string.

A big drop of radius R is formed from 1000 droplets of water. The radius of a droplet will be _______

A) 10 R

B) R/10

C) R/100

D) R/1000

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?

Show variation of displacement, velocity, and acceleration with phase for a particle performing linear S.H.M. graphically, when it starts from the extreme position.

State any two characteristics of the angle of contact

Show the formation of stationary waves diagramatically

In the stationary wave, the distance between a node and its adjacent antinode is _______.

(a) λ

(b) `lambda/4`

(c) `lambda/2`

(d)  2λ

In Melde’s experiment, when the tension in the string is 10 g wt then three loops are obtained. Determine the tension in the string required to obtain four loops, if all other conditions are constant.

Calculate the work done in increasing the radius of a soap bubble in air from 1 cm to 2 cm. The surface tension of soap solution is 30 dyne/cm. (Π = 3.142).

State the differential equation of linear simple harmonic motion.

Hence obtain the expression for acceleration, velocity and displacement of a particle performing linear S.H.M.

The electron in the hydrogen atom is moving with a speed of 2.3x10⁶ m/s in an orbit of radius 0.53 Å. Calculate the period of revolution of the electron. (Π = 3.142)

The refractive indices of water and diamond are `4/3` and 2.42 respectively. Find the speed of light in water and diamond. (c = 3x10⁸ m/s)

When a sparingly soluble substance like alcohol is dissolved in water, surface tension of water

Using an expression for energy of electron, obtain the Bohr’s formula for hydrogen spectral lines.

Explain the formation of stationary waves by analytical method. Show that nodes and antinodes are equally spaced in stationary waves.

State how a moving coil galvanometer can be converted into an ammeter.

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

Answer in brief:

A uniform disc and a hollow right circular cone have the same formula for their M.I. when rotating about their central axes. Why is it so?