An object may be regarded to be rest or in motion depending on the frame of reference chosen to view the object. Because of length contraction it would mean that the same rod may have two dfferent lenghts depending on the state of the observe. Is this true ?

When a particle is undergoing motion, the diplacement of the particle has a magnitude that is equal to or smaller than the total distance travelled by the particle. In many cases the displacement of the particle may actually be zero, while the distance travelled by it is non-zero. Both these quantities, however depend on the frame of reference in which motion of the particle is being observed. Consider a particle which is projected in the earth's gravitational field, close to its surface, with a speed of 100sqrt(2) m//s , at an angle of 45^(@) with the horizontal in the eastward direction. Ignore air resistance and assume that the acceleration due to gravity is 10 m//s^(2) . The motion of the particle is observed in two different frames: one in the ground frame (A) and another frame (B), in which the horizontal component of the displacement is always zero. Two observers locates in these frames ill agree on :-

When a particle is undergoing motion, the diplacement of the particle has a magnitude that is equal to or smaller than the total distance travelled by the particle. In many cases the displacement of the particle may actually be zero, while the distance travelled by it is non-zero. Both these quantities, however depend on the frame of reference in which motion of the particle is being observed. Consider a particle which is projected in the earth's gravitational field, close to its surface, with a speed of 100sqrt(2) m//s , at an angle of 45^(@) with the horizontal in the eastward direction. Ignore air resistance and assume that the acceleration due to gravity is 10 m//s^(2) . There exists a frame (D) in which the distance travelled by the particle is minimum. This minimum distance is equal to :-

When a particle is undergoing motion, the diplacement of the particle has a magnitude that is equal to or smaller than the total distance travelled by the particle. In many cases the displacement of the particle may actually be zero, while the distance travelled by it is non-zero. Both these quantities, however depend on the frame of reference in which motion of the particle is being observed. Consider a particle which is projected in the earth's gravitational field, close to its surface, with a speed of 100sqrt(2) m//s , at an angle of 45^(@) with the horizontal in the eastward direction. Ignore air resistance and assume that the acceleration due to gravity is 10 m//s^(2) . Consider an observer in frame D (of the previous question), who observes a body of mass 10 kg acelerating in the upward direction at 30 m//s^(2) (w.r.t. himself). The net force acting on this body, as observed from the ground is :-

When a particle is undergoing motion, the diplacement of the particle has a magnitude that is equal to or smaller than the total distance travelled by the particle. In many cases the displacement of the particle may actually be zero, while the distance travelled by it is non-zero. Both these quantities, however depend on the frame of reference in which motion of the particle is being observed. Consider a particle which is projected in the earth's gravitational field, close to its surface, with a speed of 100sqrt(2) m//s , at an angle of 45^(@) with the horizontal in the eastward direction. Ignore air resistance and assume that the acceleration due to gravity is 10 m//s^(2) . " A third observer (C) close to the surface of the reports that particle is initially travelling at a speed of 100sqrt(2) m//s making on angle of 45^(@) with the horizontal, but its horizontal motion is northward". The third observer is moving in :-

Distance is a scalar quantity. Displacement is a vector quqntity. The magnitude of displacement is always less than or equal to distance. For a moving body displacement can be zero but distance cannot be zero. Same concept is applicable regarding velocity and speed. Acceleration is the rate of change of velocity. If acceleration is constant, then equations of kinematics are applicable for one dimensional motion under the gravity in which air resistance is considered, then the value of acceleration depends on the density of medium. Each motion is measured with respect of frame of reference. Relative velocity may be greater // smaller to the individual velocities. A particle moves from A to B. Then the ratio of distance to displacement 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 -

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-

Distance is a scalar quantity. Displacement is a vector quqntity. The magnitude of displacement is always less than or equal to distance. For a moving body displacement can be zero but distance cannot be zero. Same concept is applicable regarding velocity and speed. Acceleration is the rate of change of velocity. If acceleration is constant, then equations of kinematics are applicable for one dimensional motion under the gravity in which air resistance is considered, then the value of acceleration depends on the density of medium. Each motion is measured with respect of frame of reference. Relative velocity may be greater // smaller to the individual velocities. A person is going 30 m north, 20m east and then 30sqrt(2) m southwest. The net displacement will be

Distance is a scalar quantity. Displacement is a vector quqntity. The magnitude of displacement is always less than or equal to distance. For a moving body displacement can be zero but distance cannot be zero. Same concept is applicable regarding velocity and speed. Acceleration is the rate of change of velocity. If acceleration is constant, then equations of kinematics are applicable for one dimensional motion under the gravity in which air resistance is considered, then the value of acceleration depends on the density of medium. Each motion is measured with respect of frame of reference. Relative velocity may be greater // smaller to the individual velocities. A particle is moving along the path y=4x^(2) . The distance and displacement from x=1 to x=2 is (nearly) :-