NEET 2021 Physics - Class 12 NEET-2021-Ph-630 Solution: In the product \( {F} = q( {v} {B}) = q {v} (B {i} + B {j} +…

QNEET-2021-Ph-630: NEET 2021 Physics - Class 12 NEET-2021-Ph-630 Solution: In the product \( {F} = q( {v} {B}) = q {v} (B {i} + B {j} +…

In the product

\vec{F} = q(\vec{v} \times \vec{B}) = q\vec{v} \times (B\hat{i} + B\hat{j} + B_0\hat{k})

For q = 1 and

\vec{v} = 2\hat{i} + 4\hat{j} + 6\hat{k}

and

\vec{F} = 4\hat{i} - 20\hat{j} + 12\hat{k}

What will be the complete expression for

\vec{B}

6\hat{i} + 6\hat{j} - 8\hat{k}

-8\hat{i} - 8\hat{j} - 6\hat{k}

-6\hat{i} - 6\hat{j} - 8\hat{k}

8\hat{i} + 8\hat{j} - 6\hat{k}

Multiple Choice Options

A $6\widehat i + 6\widehat j - 8\widehat k$ 6 i + 6 j _ _ 8 k
B $- 8\widehat i - 8\widehat j - 6\widehat k$ _ 8 i _ 8 j _ _ 6 k
C $- 6\widehat i - 6\widehat j - 8\widehat k$ _ 6 i _ 6 j _ _ 8 k
D $8\widehat i + 8\widehat j - 6\widehat k$ 8 i + 8 j _ _ 6 k

Step-by-Step Verified Solution

Given q = 1 and v _ = 2 i ^ + 4 j ^ + 6 k ^ and F _ = 4 i ^ _ 20 j ^ + 12 k ^ Also given, F _ = q ( v _ _ B _ ) = q v _ _ ( B i ^ + B j ^ + B 0 k ^ ) _ ( 4 i ^ _ 20 j ^ + 12 k ^ ) = _ 1 _ [ ( 2 i ^ + 4 j ^ + 6 k ^ ) _ ( B i ^ + B j ^ + B 0 k ^ ) ] Thus, calculating values of RHS, v _ _ B _ = | i ^ j ^ k ^ 2 4 6 B B B 0 | = i ^ (4B 0 - 6B) - j ^ (2B 0 - 6B) + k ^ (2B - 4B) Comparing L.H.S and R.H.S, 4B 0 � 6B = 4 .....(1) �(2B 0 � 6B)= �20 .....(2) 2B � 4B = 12 _ B = �6 .....(3) From (2) and (3) B = �6 and B 0 = �8 _ B _ = _ 6 i ^ _ 6 j ^ _ 8 k ^

QNEET-2021-Ph-630: NEET 2021 Physics - Class 12 NEET-2021-Ph-630 Solution: In the product \( {F} = q( {v} {B}) = q {v} (B {i} + B {j} +…

Multiple Choice Options

Step-by-Step Verified Solution

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