HSC Science (Computer Science) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions for Physics

Obtain an expression for the decay law of radioactivity. Hence show that the activity A(t) =λN_O e^-λt.  

Obtain an expression for magnetic induction of a toroid of ‘N’ turns about an axis passing through its centre and perpendicular to its plane.

A conducting rod along the equator is 1 m long and carries a current of 15 A from east to west. The magnitude of Earth's magnetic field at the equator is `4/3 xx 10^(-4)` T. The magnitude and direction of the force on the rod are ______.

Why does hot soap water help to remove tough stains on a fabric?

The half-life of `""_82^210Pb` is 22.3 y. How long will it take for its activity 0 30% of the initial activity?

For a solenoid and a toroid, the number of turns per unit length is n and the respective interior volume is V. The self inductance is proportional to n² and V for ______.

A current of 10 A passes through a coil having 5 turns and produces magnetic field at the centre of the coil having magnitude 0.5 x 10^-4 T. Calculate diameter of the coil.

(µ₀ = 4π x 10^-7 Wb/Am)  

Why a detergent powder is mixed with water to wash clothes?

For polyatomic molecules having 'f' vibrational modes, the ratio of two specific heats,Cp/Cv  is..........

On what factors do the degrees of freedom depend?

State the law of equipartition of energy and hence calculate the molar specific heat of mono-atomic and di-atomic gases at constant volume and constant pressure.

Show that the average energy of the molecules of a gas is directly proportional to the absolute temperature of the gas. 

Determine the molecular kinetic energy (i) per mole (ii) per gram (iii) per molecule of nitrogen molecules at 227°C, R = 8.310 J mole^-1 K^-1,No = 6.03 x 10²⁶ moleculesKmole^-1. Molecular weight of nitrogen = 28. 

When a thin hollow sphere rolls without slipping on a flat surface, the fraction of its total energy associated with rotation is ______.

The law of equipartition of energy is valid for ______.

Explain the rise of liquid in the capillary on the basis of pressure difference.

Calculate the density of paraffin oil, if glass capillary of diameter 0.25 mm dipped in paraffin oil of surface tension 0.0245 N/m rises to a height of 4 cm. (Angle of contact of paraffin with glass = 28^° and acceleration due to gravity = 9.8 m/s².)

Draw a neat, labelled diagram for a liquid surface in contact with a solid, when the angle of contact is acute.

Two soap bubbles have radii in the ratio 4:3. What is the ratio of work done to blow these bubbles?