In the light clocks, time ticks via the motion of light and since speed of light is constant therefore when the clock is in motion ,the photon has to cover a greater distance by the perspective of an object at rest . So in the perspective of object in rest time ticks at slow rate but in other clocks such as mechanical clocks .time ticks via the motion of different objects not light. and the speed of the objects are not constant.so from the perspective of an object at rest time ticks at the same rate. How can be this possible as time dilation affects all clocks?
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I like this question because it contains several common misconceptions about relativity, which, if not dispelled, will hinder progress.
Misconception 1: Motion affects the internal mechanism of clock. Clocks measure time, and their function is not affected by motion.
Misconception 2: Moving clocks run slow. The clocks don't run slow, time runs slow, but there is a caveat.
Misconception 3: Time runs slow in the moving frame. Time does not run slow in the moving frame, because in the moving frame, the moving frame is at rest, so everything is normal.
For misconceptions 1-3 to be correct, there would have to be an absolute rest frame, and a major element of SR is that there is no absolute rest frame.
The point of the light clock is that it is unambiguous. Under the axiom that $c$ is constant in all reference frames.
For clarity, put the clock in frame $S$ where it measures the passage of time properly. In a frame $S'$ moving relative to $S$, the clock ticks slower. For this to be self consistent, $S'$ has to have different space-time coordinates from $S$.
Note, I didn't say which frame was moving, because it doesn't matter. There is no absolute rest frame, so it can't even be defined.
Right now, there are reference frames (say riding a straight section of the LHC, or an ultra high energy cosmic ray) that measure UTC to be ticking at nano-seconds per second (order of magnitude), and that has absolutely no affect on us.
No matter how fast another frame sees you moving, you still live in a flat Minkowski spacetime, with light pulses moving at $c$ in all direction, because you cannot move relative to space.
JEB
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The answer is that if you have two events that occur in the same place in one frame, then the time interval between them is always less in that frame than in any other frame in which they occur in two different places. Note it is the time interval itself that is shorter. For example, the interval might be four seconds in one frame and six seconds in the other. Any type of clock will therefore measure the time accordingly.
Professor Sushing
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