If a fly collides with the windshield of a fast-mocing but, `(AS_(2))`
(a) Is the impact force experienced, same for the fly and the bus? Why
(b) It is same acceleration experience by thte fly and the bus? Why?

why Morgan selected fly for its experiment ?

(a) Magnetic field lines show the direction (at every point) along which a small magnetised needle aligns at the point). Do the magnetic field lines also represent the lines of force on a moving charged particle at every point? (b) Magnetic field lines can be entirely confined within the core of a toroid, but not within a straight solenoid. Why? (c) If magnetic monopoles existed, how would the Gauss's law of magnetism be modified? (d) Does a bar magnet exert a torque on itsell due to its own field? Does one element of a current-carrying wire exert a force on another element of the same wtre? (e) Magnetic field arises due to charges in motion. Can a system have magnetic moments even though its net charge is zero?

A man is 48m behind a bus which is at rest. The bus starts accelerating at the rate of 1 m/ s^(2) , at the same time the man starts running with uniform velocity of 10 m/s. What is the minimum time in which the man catches the bus? (8s) (AS_(7))

A cord of negligible mass is wound round the rim of a fly wheel of mass 20 kg and radius 20 cm. A steady pull of 25 N is applied on the cord as shown in Fig. 7.35. The flywheel is mounted on a horizontal axle with frictionless bearings. (a) Compute the angular acceleration of the wheel. (b) Find the work done by the pull, when 2m of the cord is unwound. (c) Find also the kinetic energy of the wheel at this point. Assume that the wheel starts from rest. (d) Compare answers to parts (b) and (c).

(a) Obtain the de Broglie wavelength of a neutron of kinetic energy 150 eV. As you have seen in Exercise 11.31, an electron beam of this energy is suitable for crystal diffraction experiments. Would a neutron beam of the same energy be equally suitable? Explain. (m_(n) = 1.675 xx 10^(-27) kg) (b) Obtain the de Broglie wavelength associated with thermal neutrons at room temperature (27^(@)C) . Hence explain why a fast neutron beam needs to be thermalised with the environment before it can be used for neutron diffraction experiments.

Explain why (a) Two bodies at different temperatures T_(1) and T_(2) if brought in thermal contact do not necessarily settle to the mean temperature (T_(1) + T_(2))//2 . (b) The coolant in a chemical or a nuclear plant (i.e., the liquid used to prevent the different parts of a plant from getting too hot) should have high specific heat. (c) Air pressure in a car tyre increases during driving. (d) The climate of a harbour town is more temperate than that of a town in a desert at the same latitude.

Explain why : (a) Two bodies at different temperatures T_1 and T_2 if brought in thermal contact do not necessarily settle to the mean temperature (T_1 + T_2 )//2 . (b) The coolant in a chemical or a nuclear plant (i.e., the liquid used to prevent the different parts of a plant from getting too hot) should have high specific heat. (c) Air pressure in a car tyre increases during driving. (d)The climate of a harbour town is more temperate than that of a town in a desert at the same latitude.

Two particles A and B move anticlockwise with the same speed v in a circle of radius R and are diametrically opposite to each other. At t=0 , A is given a constant accelerartion (tangential) a_(t)=(72v^(2))/(25 pi R) . Calculate the time in which a collides with B, the angle traced by A, its angular velocity and radial acceleration at the time of collision.