Hi all, I am not so good in physics. Plz forgive me if i am totally wrong. However, i just want to understand the time dilation thing. I referred the net, but couldn't get a convincing answer. Please explain how the time in two clocks in different inertial frame of reference can show different times? Explain in the context of following experiment. Assume that: 1) There are only 2 axes X and Y 2) I have a clock that measures time using a particle (inside it) oscillating along Y axis. Say 1 oscillation(up+down) happens in 1 second. 3) There are 2 persons(P1 and P2) each with one clock. 4) both are at (0,0) initially 5) Assume, there are no gravitational or electromagnetic forces acting on the experimental objects. Now, 1) P1 is stationary with his clock and P2 is moving along +X. 2) After 10 oscillations in P1s clock, say P2 is at (+d,0). 3) Here even P2s clock would have oscillated only 10 times right? But according to time dilation it says that time in P2s clock will be slower. How is it possible ? By time, here i mean number of oscillations along Y. Lets not bring into this discussion, the following concepts 1) that speed of light is constant in whatever frame of reference. (im using oscillation of particle with solid mass for measuring time) 2) that moving objects increase in mass Thanks for ur patience. Now answer.