HSC Science (Computer Science) १२ वीं कक्षा - Maharashtra State Board Question Bank Solutions

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?

Are Kirchhoff’s laws applicable to both AC and DC currents?

Answer in Brief:

Part of a racing track is to be designed for curvature of 72m. We are not recommending the vehicles to drive faster than 216 kmph. With what angle should the road be tilted? By what height will its outer edge be, with respect to the inner edge if the track is 10 m wide?

A road is constructed part of a racing tracks to be designed with radius of curvature 72 m. We are not recommending the vehieles to drive faster than 216 kmph.. The coefficient of static friction between the tyres of a vehicle on this road is 0.8, will there be any lower speed limit? By how much can the upper speed limit exceed in this case?

(Given: r = 72 m, vo = 216 km/h, w = 10 m, θ = 78°4', h = 9.805 m)

During a stunt, a cyclist (considered to be a particle) is undertaking horizontal circles inside a cylindrical well of radius 6.05 m. If the necessary friction coefficient is 0.5, how much minimum speed should the stunt artist maintain? The mass of the artist is 50 kg. If she/he increases the speed by 20%, how much will the force of friction be?

A pendulum consisting of a massless string of length 20 cm and a tiny bob of mass 100 g is set up as a conical pendulum. Its bob now performs 75 rpm. Calculate kinetic energy and increase in the gravitational potential energy of the bob. (Use π² = 10)

Two cells of emf 1.5 Volt and 2 Volt having respective internal resistances of 1 Ω and 2 Ω are connected in parallel so as to send current in the same direction through an external resistance of 5 Ω. Find the current through the external resistance.

A metallic ring of mass 1 kg has a moment of inertia 1 kg m² when rotating about one of its diameters. It is molten and remolded into a thin uniform disc of the same radius. How much will its moment of inertia be, when rotated about its own axis.

The energy stored in a soap bubble of diameter 6 cm and T = 0.04 N/m is nearly ______.

Why is the surface tension of paints and lubricating oils kept low?

How much amount of work is done in forming a soap bubble of radius r?

Explain the capillary action.