Measured speed vs actual speed very simple

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In summary, the conversation discusses the difference between measured speed and actual speed when using two movement detectors at different angles. It is noted that the detector not directly in the movement line sees a bigger speed due to the hypotenuse being longer. The conversation also mentions the projection of the velocity vector onto the broken line and how it affects the magnitude of the speed. More information may be needed to calculate the difference between measured and actual speed.
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asfd
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Measured speed vs actual speed **very simple**

If we measure the speed of a moving object with two movement detector positioned as on the atttached drawing, i.e. one is facing the movement and the other makes a slight angle with the movement, does the detector not directly in the movement line "sees" a bigger speed since if we see this as a trinangle the hypotenuse is bigger than any other side. If so how can we calculate the difference(what other info do we need?)?
 

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asfd said:
If we measure the speed of a moving object with two movement detector positioned as on the atttached drawing, i.e. one is facing the movement and the other makes a slight angle with the movement, does the detector not directly in the movement line "sees" a bigger speed since if we see this as a trinangle the hypotenuse is bigger than any other side. If so how can we calculate the difference(what other info do we need?)?

The out of line detector sees the projection of the velocity vector onto the broken line. The magnitude of the projection is less than or equal to the original vector.
 

What is the difference between measured speed and actual speed?

Measured speed refers to the speed recorded by a measuring device, such as a speedometer or radar gun. Actual speed, on the other hand, is the true speed at which an object is moving. This may differ from the measured speed due to factors such as measurement error or external forces like wind or friction.

Why do measured speeds sometimes differ from actual speeds?

There are several reasons why measured speeds may differ from actual speeds. One common reason is measurement error, which can be caused by faulty equipment or human error. Environmental factors, such as wind or road conditions, can also affect the accuracy of measured speeds.

How are speeds typically measured?

Speeds can be measured using a variety of methods, including radar guns, lidar (light detection and ranging) devices, and speedometers. These devices use different techniques, such as measuring the time it takes for an object to travel a known distance, to determine the speed of a moving object.

Do different types of objects have different measured speeds compared to actual speeds?

Yes, the measured speed of an object may differ from its actual speed depending on its size, shape, and other physical characteristics. For example, a car's speed may be affected by its aerodynamics, while a human's speed may be influenced by their body mass and muscle strength.

How can we ensure accurate measurements of speed?

To ensure accurate measurements of speed, it is important to use properly calibrated equipment and follow standardized measurement procedures. It is also important to consider and account for any external factors that may affect the accuracy of the measurement. Regular maintenance and calibration of measuring devices can also help to ensure accurate results.

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