The length of a meter rod moving with a velocity equal to 3×10^8 m/s appears to an observer at rest as
Correct answer: D. zero
- A. 1 m
- B. 1/2 m
- C. 1/4 m
- D. zero
Explanation
According to the theory of special relativity, objects in motion appear contracted in the direction of motion to an observer at rest. This contraction is known as length contraction. As the velocity approaches the speed of light, the length contraction becomes significant. Therefore, the length of the meter rod appears contracted to zero from the perspective of an observer at rest.Incorrect Options and Explanations: (a) 1 m - This is not the correct length contraction observed at relativistic velocities. (b) 1/2 m - This option does not account for the significant length contraction observed at relativistic velocities. (c) 1/4 m - This option does not account for the significant length contraction observed at relativistic velocities.(21) In a certain circuit, a collector current of 10 mA and a base current of 40 µA. What is the current gain of the transistor?
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Progressive waves transfer energy through oscillations, with wavelength, frequency, amplitude and wave speed related by v = fλ; sound speed depends on the medium. Superposition produces interference and stationary waves in strings and organ pipes, while simple harmonic motion describes the oscillation itself and must be distinguished from wave propagation.
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