It is sometimes heard that inertial frame of reference is only an ideal concept and no such inertial frame actually exists. Comment.

Define frame of reference and give its types.

Assertion :- Newton's first law defines inertial frame of reference. Reason :- Newton's laws can be applied only in inertial frames of reference.

The magnetic force depends on v which depends on the inertial frame of reference. Does then the magnetic force differ from inertial frame to frame ? Is it reasonable that the net acceleration has a different value in different frames of reference ?

A frame of reference that is accelerated with respect to an inertial frame of reference is called a non-inertial frame of reference. A coordinate system fixed on a circular disc rotating about a fixed axis with a constant angular velocity omega is an example of non=inertial frame of reference. The relationship between the force vecF_(rot) experienced by a particle of mass m moving on the rotating disc and the force vecF_(in) experienced by the particle in an inertial frame of reference is vecF_(rot)=vecF_(i n)+2m(vecv_(rot)xxvec omega)+m(vec omegaxx vec r)xxvec omega . where vecv_(rot) is the velocity of the particle in the rotating frame of reference and vecr is the position vector of the particle with respect to the centre of the disc. Now consider a smooth slot along a diameter fo a disc of radius R rotating counter-clockwise with a constant angular speed omega about its vertical axis through its center. We assign a coordinate system with the origin at the center of the disc, the x-axis along the slot, the y-axis perpendicular to the slot and the z-axis along the rotation axis (vecomega=omegahatk) . A small block of mass m is gently placed in the slot at vecr(R//2)hati at t=0 and is constrained to move only along the slot. The distance r of the block at time is

A frame of reference that is accelerated with respect to an inertial frame of reference is called a non-inertial frame of reference. A coordinate system fixed on a circular disc rotating about a fixed axis with a constant angular velocity omega is an example of non=inertial frame of reference. The relationship between the force vecF_(rot) experienced by a particle of mass m moving on the rotating disc and the force vecF_(in) experienced by the particle in an inertial frame of reference is vecF_(rot)=vecF_(i n)+2m(vecv_(rot)xxvec omega)+m(vec omegaxx vec r)xxvec omega . where vecv_(rot) is the velocity of the particle in the rotating frame of reference and vecr is the position vector of the particle with respect to the centre of the disc. Now consider a smooth slot along a diameter fo a disc of radius R rotating counter-clockwise with a constant angular speed omega about its vertical axis through its center. We assign a coordinate system with the origin at the center of the disc, the x-axis along the slot, the y-axis perpendicular to the slot and the z-axis along the rotation axis (vecomega=omegahatk) . A small block of mass m is gently placed in the slot at vecr(R//2)hati at t=0 and is constrained to move only along the slot. The distance r of the block at time is

Assertion: The driver in a vechicle moving with a constant speed on a straight road is in a non-inertial frame of referance. Reason: A reference frame in which Newton's laws of motion are applicable is non-inertial.

Einstein in 1905 proppunded the special theory of relativity and in 1915 proposed the general theory of relativity. The special theory deals with inertial frames of reference. The general theory of relativity deals with problems in which one frame of reference. He assumed that fixed frame is accelerated w.r.t. another frame of reference of reference cannot be located. Postulated of special theory of realtivity ● The laws of physics have the same form in all inertial systems. ● The velocity light in empty space is a unicersal constant the same for all observers. ● Einstein proved the following facts based on his theory of special relativity. Let v be the velocity of the speceship w.r.t a given frame of reference. The obserations are made by an observer in that reference frame. ● All clocks on the spaceship wil go slow by a factor sqrt(1-v^(2)//c^(2)) ● All objects on the spaceship will have contracted in length by a factor sqrt(1-v^(2)//c^(2)) ● The mass of the spaceship increases by a factor sqrt(1-v^(2)//c^(2)) ● Mass and energy are interconvertable E = mc^(2) The speed of a meterial object can never exceed the velocity of light. ● If two objects A and B are moving with velocity u and v w.r.t each other along the x -axis, the relative velocity of A w.r.t. B = (u-v)/(1-uv//v^(2)) The momentum of an electron moving with a speed 0.6 c (Rest mass of electron is 9.1 xx 10^(-31 kg )

Einstein in 1905 proppunded the special theory of relativity and in 1915 proposed the general theory of relativity. The special theory deals with inertial frames of reference. The general theory of relativity deals with problems in which one frame of reference. He assumed that fixed frame is accelerated w.r.t. another frame of reference of reference cannot be located. Postulated of special theory of realtivity ● The laws of physics have the same form in all inertial systems. ● The velocity light in empty space is a unicersal constant the same for all observers. ● Einstein proved the following facts based on his theory of special relativity. Let v be the velocity of the speceship w.r.t a given frame of reference. The obserations are made by an observer in that reference frame. ● All clocks on the spaceship wil go slow by a factor sqrt(1-v^(2)//c^(2)) ● All objects on the spaceship will have contracted in length by a factor sqrt(1-v^(2)//c^(2)) ● The mass of the spaceship increases by a factor sqrt(1-v^(2)//c^(2)) ● Mass and energy are interconvertable E = mc^(2) The speed of a meterial object can never exceed the velocity of light. ● If two objects A and B are moving with velocity u and v w.r.t each other along the x -axis, the relative velocity of A w.r.t. B = (u-v)/(1-uv//v^(2)) One cosmic ray particle appraches the earth along its axis with a velocity of 0.9c towards the north the and another one with a velocity of 0.5c towards the south pole. The relative speed of approcach of one particle w.r.t. another is-

Einstein in 1905 proppunded the special theory of relativity and in 1915 proposed the general theory of relativity. The special theory deals with inertial frames of reference. The general theory of relativity deals with problems in which one frame of reference. He assumed that fixed frame is accelerated w.r.t. another frame of reference of reference cannot be located. Postulated of special theory of realtivity ● The laws of physics have the same form in all inertial systems. ● The velocity light in empty space is a unicersal constant the same for all observers. ● Einstein proved the following facts based on his theory of special relativity. Let v be the velocity of the speceship w.r.t a given frame of reference. The obserations are made by an observer in that reference frame. ● All clocks on the spaceship wil go slow by a factor sqrt(1-v^(2)//c^(2)) ● All objects on the spaceship will have contracted in length by a factor sqrt(1-v^(2)//c^(2)) ● The mass of the spaceship increases by a factor sqrt(1-v^(2)//c^(2)) ● Mass and energy are interconvertable E = mc^(2) The speed of a meterial object can never exceed the velocity of light. ● If two objects A and B are moving with velocity u and v w.r.t each other along the x -axis, the relative velocity of A w.r.t. B = (u-v)/(1-uv//v^(2)) A stationary body explodes into two fragments each of rest mass 1 kg that move apart at speed of 0.6c relative to the original body. The rest mass of the original body is -

A frame will be inertial, if it moves with respect to another inertial frame with a constant :-