HSC Science (General) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions

A car of mass 1500Kg rounds a curve of radius 250m at 90 Km/hour. Calculate the centripetal force acting on it.

A particle of mass m, just completes the vertical circular motion. Derive the expression for the difference in tensions at the highest and the lowest points.

Explain the concept of centripetal force.

Obtain an expression for the torque acting on a rotating body with constant angular acceleration. Hence state the dimensions and SI unit of torque.

In Doppler effect of light, the term “red shift” is used for ______.

(A) frequency increase

(B) frequency decrease

(C) wavelength decrease

(D) frequency and wavelength increase

Doppler effect is not applicable when _______.
(A) source and observer are at rest.
(B) there is a relative motion between source and observer.
(C) both are moving in opposite directions.
(D) both are moving in same direction with different velocities

The working of RADAR is based on ...............

a) resonance

b) speed of a star

c) Doppler effect

d) speed of rotation of sun

Obtain an expression for torque acting on a body rotating with uniform angular acceleration.

From earth's surface, ionospheric layer of atmosphere lies between ............

(a) 12 km to 50 km

(b) 50 km to 80 km

(c) 80 km to 400 km

(d) 400 km to 700 km

A racing car completes 5 rounds of a circular track in 2 minutes. Find the radius of the track
if the car has uniform centripetal acceleration of Π² m/s².

Apparent frequency of the sound heard by a listener is less than the actual frequency of sound emitted by source. In this case _______.

(A) listener moves towards source

(B) source moves towards listener

(C) listener moves away from the source.

(D) source and listener move towards each other.

Obtain an expression for the induced e.m.f. in a coil rotating with uniform angular velocity in
uniform magnetic field. Plot a graph of variation of induced e.m.f. against phase (Θ = ωt) over one cycle.

State any four applications of Doppler effect

Define moment of inertia. State its SI unit and dimensions.

At which position of the plane of the rotating coil with the direction of magnetic field, the e.m.f. induced in the coil is maximum?

State Brewster’s law and show that when light is incident at polarizing angle the reflected and refracted rays are mutually perpendicular to each other.

Soft iron is used to make the core of the transformer because of its ______.

Which property of soft iron makes it useful for preparing electromagnet?

What should be retentivity and coercivity of permanent magnet?

Answer in brief.

Explain one application of electromagnet.