While using equations of circular motion why do we need to express all

Thread starter Shivam123
Start date Sep 4, 2011
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Circular Circular motion Motion

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In circular motion equations, angles must be expressed in radians to ensure accuracy, as the formula s = rθ (arc-length equals radius times angle) only holds true in this unit. Radians are essential because they relate directly to the properties of circles, specifically the relationship between circumference and radius, expressed as 2πr. This connection allows for consistent calculations across various applications of circular motion. Using radians simplifies the mathematical relationships and ensures that results are dimensionally consistent. Understanding the necessity of radians is crucial for correctly applying circular motion equations.

Sep 4, 2011

Shivam123

while using equations of circular motion why do we need to express all angles in radians?

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Sep 4, 2011

BruceW

Science Advisor

s = r \theta (i.e. arc-length equals radius times angle) is only true when the angle is expressed in radians.
In other words, we know that \pi is a special number, such that the circumfrence equals 2 \pi r for any circle. And so we use radians to make use of this special number.

Sep 4, 2011

Shivam123

good..got it thanks

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