# What is F.D?

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what is f vector dot ds vector

options are

A)Torque

B)Impulse

C)Momentum

D)Work

Edited by Jay Sharma
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There is not enough information there to give a better answer than

A scalar.

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There is not enough information there to give a better answer than

A scalar.

ok so it means that it is work done since that is the only scalar whose equation is this

any more suggestions??

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Do you mean $f \cdot ds$? And, is f a vector field?

If the above is true, $f \cdot ds$ is just the dot product of the vector field f and an infinitesimal length ds.

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Force over a distance travelled is work done. Is this what you were looking at?

https://en.wikipedia.org/wiki/Work_%28physics%29

$W=F.d$

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what is f vector dot ds vector

Considering what you have revealed about your status elsewhere I guess that you have not yet studied vectors in detail.

So you may be asking what is the dot product all about, as distinct from what is the particular dot product.

If that is the case then the following may help.

Ordinary numbers (scalars) have one single type of product.

5 x 3 is always 15 and that is all there is to it.

Vectors, on the other hand have three distinct types of product.

The simplest is the product of a scalar and a vector eg (aZ ) which results in another vector a times the magnitude of Z but along the same line of action.

This product is called the multiplication of a vector by a scalar (it is not the so called scalar product)

The second also results in another vector and comes from multiplying two vectors together. This product is more complicated as it results in a single new vector that is at right angles to the plane containing the original vectors and of magnitude Z = X x Ysin(a) where a is the angle between them.

This product is called the vector or cross product.

The product you are asking about is called the scalar or dot product.

The result of the dot product is a scalar (with no direction) of magnitude m = X . Y cos(a) where a is again the angle between them

In your original question F and ds are both vectors. Note I have used bold to show vectors, a common convention.

Does this help?

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Force over a distance travelled is work done. Is this what you were looking at?

https://en.wikipedia.org/wiki/Work_%28physics%29

$W=F.d$

ok so is it f vector dot d vector??

Considering what you have revealed about your status elsewhere I guess that you have not yet studied vectors in detail.

So you may be asking what is the dot product all about, as distinct from what is the particular dot product.

If that is the case then the following may help.

Ordinary numbers (scalars) have one single type of product.

5 x 3 is always 15 and that is all there is to it.

Vectors, on the other hand have three distinct types of product.

The simplest is the product of a scalar and a vector eg (aZ ) which results in another vector a times the magnitude of Z but along the same line of action.

This product is called the multiplication of a vector by a scalar (it is not the so called scalar product)

The second also results in another vector and comes from multiplying two vectors together. This product is more complicated as it results in a single new vector that is at right angles to the plane containing the original vectors and of magnitude Z = X x Ysin(a) where a is the angle between them.

This product is called the vector or cross product.

The product you are asking about is called the scalar or dot product.

The result of the dot product is a scalar (with no direction) of magnitude m = X . Y cos(a) where a is again the angle between them

In your original question F and ds are both vectors. Note I have used bold to show vectors, a common convention.

Does this help?

thnx for that that helped

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ok so is it f vector dot d vector??

..

Well last time I looked both Force and displacement were both vectors. Remember you get no result with a dot product if the vectors are perpendicular - and that tallies with the fact that no work done when force act orthogonally to the motion.

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Well last time I looked both Force and displacement were both vectors. Remember you get no result with a dot product if the vectors are perpendicular - and that tallies with the fact that no work done when force act orthogonally to the motion.

ok so is the answer among the options is work done????

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!

Moderator Note

Members should be aware that the OP Jay Sharma has been banned as a sockpuppet of Rajnish Kaushik.

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if i m not wrong than f is force and d is displacement so according to dimensions work done is correct

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I know that he has been banned again (this time in the guise of Maddy) but It might be worth pointing out that my reply to the OP was made when it only said

"what is f vector dot ds vector"

Since it's a dot product, you know it's a scalar quantity.

I'm not certain, but I think that is enough to answer the question once you know what the options are.

BTW, Maddy/ Jay / Rajnish Kaushik

it's bad manners to change your post like that after someone has replied.

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