How to Find the Modulus of Velocity and Acceleration?

Thread starter ritwik06
Start date Jun 18, 2008
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Point Radius Vector

AI Thread Summary

To find the modulus of velocity and acceleration from the given radius vector $\vec{r}=\vec{c}t+\vec{b}\frac{t^{2}}{2}$, the velocity is calculated as $\vec{v}=\vec{c}+\vec{b}t$ and the acceleration as $\vec{a}=\vec{b}$. The modulus of the velocity is determined using the formula $|\vec{v}|=\sqrt{\vec{v} \cdot \vec{v}}$, and similarly, the modulus of the acceleration is $|\vec{a}|=\sqrt{\vec{a} \cdot \vec{a}}$. The discussion emphasizes the need to apply the dot product to find these moduli. Understanding these calculations is crucial for analyzing motion in physics.

Jun 18, 2008

ritwik06

Homework Statement

The radius vector of a point depends on time t, as \vec{r}=\vec{c}t+\vec{b}\frac{t^{2}}{2}, where \vec{c} and \vec{b} are constant vectors. Find the modulus of velocity and acclereation at any time t.

The Attempt at a Solution

\vec{v}=\vec{c}+\vec{b}t

\vec{a}=\vec{b}

But how shall I find the modulus?

Last edited: Jun 18, 2008

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Jun 18, 2008

Dick

Science Advisor

Homework Helper

The modulus of a vector v is the square root of v dot v.

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