JEE Mains · Physics · STD 11 - 4.1 newtons laws of motion
At any instant the velocity of a particle of mass \(500\,g\) is \(\left(2 t \hat{ i }+3 t ^2 \hat{ j }\right)\,ms ^{-1}\). If the force acting on the particle at \(t=1 s\) is \((\hat{i}+x \hat{j}) N\). Then the value of \(x\) will be:
- A \(3\)
- B \(4\)
- C \(6\)
- D \(2\)
Answer & Solution
Correct Answer
(A) \(3\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ v }=2 t \hat{ i }+3 t ^2 \hat{ j }\) \(\overrightarrow{ a }=2 \hat{i}+6 t \hat{j}\) at \(t=1, \vec{a}=2 \hat{i}+6 \hat{j}\) \(\overrightarrow{ F }= ma =0.5(2 \hat{i}+6 \hat{j})=\hat{i}+3 \hat{j}\)…
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