Physics XI Content
COMMUTATIVE LAW FOR DOT PRODUCT
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COMMUTATIVE LAW FOR DOT PRODUCT | |||
| This law states that : | |||
“The scalar product of two vectors  and  is equal to the magnitudeof vector times the projection of onto the direction of vector . “ | |||
| Consider two vectors and ,the angle between them is q. | |||
 | |||
where  represents the projection of vector onto the direction of vector . | |||
| Similarly, | |||
 | |||
Where  represents the projection of vector onto the direction of vector . | |||
| Since | |||
 | |||
| This shows that the dot product of two vectors does not chanfe with the change in the order of the vectors to be multiplied. This fact is known as the commutative of dot product. | |||
