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QJEEM24Ph1f6f: JEE Main 2024 Physics - Class 11 JEEM24Ph1f6f Solution: A vector has magnitude same as that of and is parallel to . The …

A vector has magnitude same as that of A⃗=3i^+4j^\vec{A}=3 \hat{i}+4 \hat{j} and is parallel to B⃗=4i^+3j^\vec{B}=4 \hat{i}+3 \hat{j} . The xx and yy components of this vector in first quadrant are xx and 3 respectively where x=x= _________.

Step-by-Step Verified Solution

To find a vector that has the same magnitude as vector A⃗\vec{A} and is parallel to vector B⃗\vec{B} , we use the formula:

N⃗=∣A⃗∣B^\vec{N} = |\vec{A}| \hat{B}

First, let's find the magnitude of A⃗\vec{A} , which is ∣A⃗∣|\vec{A}| .

∣A⃗∣=32+42=5|\vec{A}| = \sqrt{3^2 + 4^2}=5

We're given that B⃗=4i^+3j^\vec{B} = 4 \hat{i}+3 \hat{j} , so to make N⃗\vec{N} parallel to B⃗\vec{B} and have it have the same magnitude as A⃗\vec{A} , they should be the same when N⃗\vec{N} 's magnitude is divided by 5, since ∣A⃗∣=5|\vec{A}|=5 .

So, N⃗=5(4i^+3j^)5=4i^+3j^\vec{N} = \frac{5(4\hat{i}+3\hat{j})}{5} = 4\hat{i}+3\hat{j} .

This means the xx component of the vector in the first quadrant is 4, and the yy component is given as 3. So, x=4x=4 .

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