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Karnataka Board PUCPUC Science Class 11

Let → a = 5 → I − 4 → J and → B = − 7 ⋅ 5 → I + 6 → J .Do We Have → B = K → a ? Can We Say → B → a = K ?

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Question

Let \[\vec{A} = 5 \vec{i} - 4 \vec{j} \text { and } \vec{B} = - 7 \cdot 5 \vec{i} + 6 \vec{j}\]. Do we have \[\vec{B} = k \vec{A}\] ? Can we say \[\frac{\vec{B}}{\vec{A}}\] = k ?

Answer in Brief
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Solution

If \[\vec{A} = 5 \vec{i} - 4 \vec{j}\text { and } \vec{B} = - 7 \cdot 5 \vec{i} + 6 \vec{j}\],then we have \[\vec{B} = k \vec{A}\] by putting the value of scalar k as \[- 1 . 5\] .

However, we cannot say that \[\frac{\vec{B}}{\vec{A}}\] = k, because a vector cannot be divided by other vectors, as vector division is not possible.

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Chapter 2: Physics and Mathematics - Short Answers [Page 28]

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HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 2 Physics and Mathematics
Short Answers | Q 14 | Page 28

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