How Fast is a Clock Moving if It Runs Four Times Slower?

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Homework Help Overview

The problem involves a moving clock that is observed to run four times more slowly than a stationary clock, prompting a question about the speed of the moving clock relative to the stationary frame. The subject area pertains to concepts in special relativity and time dilation.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss relevant equations for time dilation and question which quantities are known and what needs to be calculated. There are attempts to manipulate the time dilation formula to find the speed of the moving clock.

Discussion Status

Participants are actively engaging with the problem, sharing their reasoning and calculations. Some have provided equations and attempted to derive the speed, while others are clarifying definitions and relationships between the variables involved. There is no explicit consensus yet, but productive lines of inquiry are being explored.

Contextual Notes

Participants are working under the constraints of the problem as posed, with assumptions about the nature of the clocks and their relative motion being discussed. The specific values and relationships in the equations are being examined without resolution.

ZedCar
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A moving clock is observed to run four times more slowly than an identical
stationary clock. What is its speed relative to the frame of the stationary clock?


I'm wondering which equation should I be using for this?

Thanks
 
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What equations do you know of that might be relevant here?
Which of the quantities in those equations are given (and what is the one you want to calculate)?
 
I've been using

t = t0 / sqrt(1 - v^2/c^2)

t = 4t / (1 - v^2/c^2)^0.5

(1 - v^2/c^2)^0.5 = 4t/t

1 - v^2/c^2 =16

-15c^2 = v^2

v = (-15c^2)^0.5
 
This is what i think it is:

delta t' = delta t/sqrt(1-(v/c)^2)

now
delta t = proper time, time interval in moving frame as measured by the moving frame
delta t' = time interval of moving frame as measured by rest frame.

So delta t' = 4 delta t, as the time interval of the moving clock is measured 4 times slower than stationary clock.

Therefore 4 = 1/sqrt(1-(v/c)^2)

Then you should be able to solve and find v as a fraction of c.
 
Thank you.

I'm now getting answer of ((15/16)^0.5)c
 

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