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Maths, Addmaths and Statistics: Post your doubts here!

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These vectors ae just unut vectors which show direction. We need to find vector. Thats why we multiply so magnitude of vector is same as the magnitude given.

Yeah, that I know that the magnitude is equal to the magnitude of the velocity vector.
BUT, my point is that, if we do it by, (3/5i + 4/5j) * 20 to get velocity vector, isn't this the wrong method?
 
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Yeah, that I know that the magnitude is equal to the magnitude of the velocity vector.
BUT, my point is that, if we do it by, (3/5i + 4/5j) * 20 to get velocity vector, isn't this the wrong method?

the magnitude of the vector u get after multiplication wont be 20. the magnitude of the vector should be 20 not multiplied by 20. for that multiply by 20 and divide by magnitude of the vector already given.
if the vector which actually not unit vector as it's magnitude is not 1.

otherway of thinking this is that first convert the vector into unit vector then multiply by 20. same result.
 
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the magnitude of the vector u get after multiplication wont be 20. the magnitude of the vector should be 20 not multiplied by 20. for that multiply by 20 and divide by magnitude of the vector already given.
if the vector which actually not unit vector as it's magnitude is not 1.

otherway of thinking this is that first convert the vector into unit vector then multiply by 20. same result.

That's what I did. The direction thing is so much more sensible.
 
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Saad did u make any mistake, my whole was 100% distinction until i came to know about a silly mstk costing me 2 marks

Not yet. ALHUMDULILLAH. There was just one thing. I gave a certain answer to 2 sig fig. rather than 3 sig. fig. :cry:
 
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