Physics

Attempt all parts of following

(a) State Lemi's theorem and elaborate it with one example.

(b) What is the inertial reference frame? Explain with example.

(c) Write the properties of friction. Why la coefficient of Kinetic friction always less than coefficient of atatic friction?

(d) Suppose a particle moves along x-axis, decide whether the K.E. of particle Increase, decrease or remain same if velocity changes -

(i) from 9 m/sec to 2 /sec             (ii) from 2 m/nee to 2 m/sec.

(e) Show that in I-D elastic collision, the relative velocity of the particle is unchanged in magnitude but is revered in direction

(f) state Gauss's law in electrostatics and show that  where   is charge density.

(g) State Kirchhol's rule and explain it.

(h) Give the postulates of Bohr Model.

(i) Write the name of current carriers in semiconductor materials. What is the effect of temperature in intrinsic semiconductore?

(j) Give the working and applications of LED.

Discuss the equilibrium of Concurrent forces with examples. A resultant force of 20 N gives a body of mass man acceleration of 8.0 m/sec, and a body of mass M an accleration of 24 m/sec. What acceleration will this force o ne two masses to acquire if fastened together? 

Define equipotential surface and equipotential lines. schematically show equipotential lines for a point charge and an electric dipole. Four charges of q, -2q, 3q and 2q are placed at the corners of a square of side 1 m. Calculate the electric potential at the centre of the square (Given:).

Explain the need for automobile seat belts in terms of Newton's first law. A horisontal cable pulls a 200 kg cart along a hormonal track. The tension in the cable is 500 N. Starting from rest, (a) bow long will it take the cart to reach a speed of 8 m/sec? How far will it have gone? 

Explain microscopic basis of friction. Consider an automobile moving along a straight horizontal road with a speed up. The driver applies the brakes and brings the car to a halt without slidding. If the coefficient of state friction between tires and road is what is the shortest distance in which the automobile can be stopped?

Why is roadbed is banked for transportation? Show that angle of banking is  where is curvature of radius and a velocity of object. A conical pendulum la formed by attaching a 53 gm pebble to a 1.4 m string The pebble swings around in a circle of radius 25 am What is the speed of pebble?

Derive the expression of Gravitational potential energy to bring an object from infinity. How much electrical energy would be used by an elevator lifting a 75 Kg person through a height of 50 m if the elevator system has overall efficiency of 25%? Assume the mass of the empty elevator car is properly balanced by a counterweight .

What is the source of frictional electricity? Give the properties of eloetric lines of force. A proton orbits with a speed 294 km/we just outside a charged sphere of radius 1.13cm. Find the charge on the sphere (m_p

What is Side wire bridge? Explain working principle with a  schematic diagram. Compare the slide wire bridge with Whea tstone bride.  

What is the effect of dielectric having inserted in parallel plate capacitor?Consider the following give circuit diagram. Answer the following questions

. 

(a) Calculate the equivalent capacitance.

(b) Calculate total charges

(c) Determine charges on individual capacitors 

State Newton's laws of motion and mention their implications.

Mention laws of limiting friction and explain now they can be verified experimentally.

Write down the laws of resistances connected in series and parallel.

What is a Gaussian surface? Mention the one widely used Gaussian surfaces and how it is produced.

Explain how a light emitting diode works.

State work-energy theorem.

Write down the postulates of Bohr's atomic model. 

State Lemi's theorem. Give one application of the theorem.

Explain the concept of banking of roads. Obtain an expression for the maximum speed a car can safely move on a curved road banked at an angle e. What is the ideal, or critical speed (the speed for which no friction is required between the car's tires and the surface) for a car moving on a curved road of radius 50 m at a banking angle of ?

A car of mass 2000 kg travels around a flat circular race track on radius r = 85 m. The car starts at rest and its speed increases at the constant rate of 0.6 m/s. What is the speed of the car at the point when its centripetal and tangential accelerations are equal?

Out of three basic Newton's law of motion, which one is the most Fundamental one and why? Discuss with the help of suitable example.

Discuss various types of friction & their possible causes. Mention some of the advantages of friction.

Differentiate between elastic and inelastic collisions and obtain an expression for the velocities after collision and the energy lost in inelastic collision between two bodies.

A body of mass 50 g moving with speed of 10 m/s undergoes an elastic collision with another body of mass 150 g at rest. Find the kinetic energies of the two bodies after head-on elastic collision.

Define conservative force and prove that gravitational force is a conservative force. Give one example of non-conservative force.

Discuss conservation of energy in an inelastic collision.

Derive an expression for electric field strength at a point due to an electric dipole.

A parallel plate capacitor has a capacitance of 112 pF, a plate area of and a mica dielectric  At a 55 V potential difference, calculate the electric field strength in the mica.

A parallel plate capacitor has a capacitance of 112 pF, a plate area of and a mica dielectric  At a 55 V potential difference, calculate the magnitude of the free charge on the plates.

A parallel plate capacitor has a capacitance of 112 pF, a plate area of and a mica dielectric  At a 55 V potential difference, calculate the magnitude of the induced surface charge.

What is Wheatstone bridge? Explain it using a schematic diagram.Why are Wheatstone Bridge circuits very important in measuring pesistance accurately?

Differentiate between metal, semiconductor and insulator Draw schematic energy level diagrams.

Explain the principle of operation of p-n junction diode using energy level diagrams. Draw the current-voltage characteristics of junction diode.

Explain the principle of operation of p-n-p transistor using schematic diagrams.

Distinguish between intrinsic and extrinsic semiconductors.Schematically show the positions of Fermi levels in an intrinsic semiconductor, an n-type and a p-type semiconductor.

State and prove work energy theorem. What is the conservative fore? The potential energy of a particle undergoing one dimensional motion along the X-axis is  Ita total energy at x-0 is 2 Joule, and it is not subject to any non-conservative force. Find (a) the positions where is Identic energy is zero (b) the force at this position.

What is completely inclastic collision? Express the kinetic energy of a particle in terms of its mass m and the magnitude of linear momentum P.A block of mass mi -4 kg and initial velocity u_i-41 m/sec makes a 1-D elastic collision with block of mass m₂-3 Kg atw, =21 m/sec. Find their final momentum,

Derive the expression of the centre of mass of two colliding bodies the target in initially stationary. An electron collides elastically with Hydrogen atom Initially at rest. What percentage of electron's initial kinetic energy la transformed to Hydrogen atom? The mass of the Hydrogen atoms 1840 Low the true of electron,

Derive an expression for electric potential at the axis of ring due to a ring of uniform line charge.

(a) What are the key failure of Thomson's atomic model? Write the conclusions of Rutherford's alpha scattering experiment

Thought Silicon an Aluminium have the same atomic density and mass density, the difference in their electrical resistivity is very high. Why? What is meant by potential barrier across a p-n junction? 

lndicate on an energy level diagram the conduction and and valence bands, donor and acceptor states. What are positions of Perm levels for (a) an intrinsic semiconductor (b) a n-type seconductor (c) a p-type semiconductor

Discuss the working of a PNP transistor as an amplifier in common base configuration. Define the current gain in common base configuration declare the expression for voltage and power gain. 

Define angle of repose and angle of friction.

 State Newton's 2nd law and derive the relation between force and momentum

State & prove Lemi's theorem Siat.

State and prove Gauss's theorem

Why two electric field lines cannot intersect each other

Define Kirchhoff's first & second law

State and explain Coulomb's law

What is Bohr's atomic model?

What is doping of an intrinsic semiconductor? Name the charge carries in p-type semiconductors? 

What do you mean by barking of road? Calculate the angle of banking so that a vehicle of mass m can go with velocity v on a curved road of radius r without skidding.

b) Calculate the weight of a body of mass m placed in lift, when the lift:

(i)Moves vertically upward with acceleration a.

(ii)Moves vertically downward with acceleration a.

(iii)Moves with constant velocity v.

(iv) At rest.

What is meant by limiting friction? Explain the laws of friction.

Two masses m1 & m2 are connected by a light string which passes over a friction less pulley such that mass m2 move vertically downward and m1 move vertically upward, calculate acceleration and tension in the string.

Prove that total energy o falling freely body under gravity will remains same at all points on its path.

b) Define conservative force. Prove that gravitational force is a conservative force. Also write the properties of conservative force.

What is Hooke's Law Calculate the Potential Energy of a spring when it is pulled to a displacement x from its mean position.

by Show that when two bodies of equal  masses suffer elastic collision in I-dimension, they will exchange their velocities.

Obtain the expression for capacitance of parallel plate capacitor with dielectric slab. 

Define electric field intensity. Calculate electric field intensity at any point on the axis of uniformly charged circular ring. 

Find the total resistance when a number of resistances are connected in series and In parallel 

Define Ohm's law. Explain the construction, working and principle & proof of wheat stone bridge with diagram in detail. 

Distinguish between Insulators, conductors and semi conductors in term of their energy band diagrams.

Explain briefly Rutherford's alpha scattering experiment and the atomic model based on the result of this experiment. 

What is p-n junction diode? Explain the action of forward bias

What is transistor? Explain construction and working n-p-n & p-n-p transistor with diagram.