If the projection of $2\hat{i}+4\hat{j}-2\hat{k}$ on $\hat{i}+2\hat{j}+\alpha\hat{k}$ is zero. Then, the value of $\alpha$ will be __________.

JEE Main 2022 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 28 July 2022, Shift 1, Physics Q51

Question 51 of 90 in this shift, Physics question 21 of 30, Section B.

If the projection of

2\hat{i}+4\hat{j}-2\hat{k}

\hat{i}+2\hat{j}+\alpha\hat{k}

is zero. Then, the value of

\alpha

will be __________.

Official answer

NTA final key (2022 Session 2).