Measuring a Rod in a Running Train: Why?

In summary, if a rod is measured in a running train, for all practical purposes, nothing will happen. However, at very small decimal places, the rod may be slightly shorter compared to when the train is not moving. This is assuming a real train on Earth, not a thought experiment at a relativistic speed. If the train is moving at 70% of the speed of light, both the rod and measuring stick will shrink, but the change will not be noticeable since they both shrink proportionally.
  • #1
vinayjain
70
0
Can anyone tell me what will happen to a length og a rod if it is measured in a running train and why?
 
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  • #2
For all practical purposes, nothing will happen. Down around the 15th decimal place or so, WAY below our ability to measure it, the rod will be shorter than if the train were not moving. This is assuming that you are talking about a real train, on earth, not a thought experiment with the train moving at a relativistic speed.
 
  • #3
yup...I am talking about a real train and thanx.....but can u please tell me if not a realistic train say if train is moving at the 70% speed of light then what will happen
 
  • #4
Well, both the rod and your measuring stick will shrink a bit but you won't notice it since they BOTH shrink.
 
  • #5


Measuring the length of a rod in a running train can produce different results compared to measuring it on a stationary train. This is because the train is in motion, which can affect the measurement due to the relative motion between the rod and the observer.

The length of the rod will appear shorter when measured in a running train. This is due to the phenomenon of length contraction, which was first proposed by Albert Einstein in his theory of relativity. According to this theory, objects in motion appear to be shorter in the direction of their motion when measured by an observer at rest.

In the case of a running train, the rod is moving with the train, and therefore, its length will appear shorter to an observer outside the train. This is because the observer is measuring the length of the rod from a frame of reference that is stationary, while the rod is moving. As a result, the measurement will be affected by the relative motion between the two frames of reference.

Furthermore, the speed of the train can also affect the measurement. The faster the train is moving, the greater the length contraction effect will be. This is because the relative speed between the rod and the observer will be higher, resulting in a greater difference in the measured length.

In conclusion, measuring a rod in a running train can produce different results due to the phenomenon of length contraction. This is a fundamental concept in the theory of relativity and is essential to consider when making precise measurements in a moving frame of reference.
 

1. Why is it important to measure a rod in a running train?

Measuring a rod in a running train is important because it allows us to accurately determine the length of the rod without any external factors affecting the measurement. This is especially important in scientific experiments where precise measurements are necessary.

2. How does one measure a rod in a running train?

To measure a rod in a running train, one must first ensure that the train is moving at a constant speed. Then, the rod can be measured using a measuring tape or ruler, taking into account the motion of the train. Alternatively, specialized equipment such as laser distance sensors can be used to measure the rod's length accurately.

3. What challenges may arise when measuring a rod in a running train?

One of the main challenges when measuring a rod in a running train is the motion of the train itself. This can cause the rod to appear longer or shorter than its actual length. Other challenges may include vibrations from the train or external factors such as wind or changes in temperature.

4. How can the accuracy of measuring a rod in a running train be improved?

To improve the accuracy of measuring a rod in a running train, it is important to use specialized equipment designed to compensate for the train's motion and other external factors. Additionally, taking multiple measurements and calculating the average can also help improve the accuracy of the measurement.

5. Are there any real-world applications for measuring a rod in a running train?

Yes, there are several real-world applications for measuring a rod in a running train. For example, this technique can be used in construction projects, where precise measurements are necessary for building structures such as bridges and tunnels. It can also be used in transportation systems, such as railways, to ensure the safety and efficiency of the train's operation.

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