JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2016
- Hard
- MCQ
A particle of mass \(m\) is moving along the side of a square of side '\(a\)', with a uniform speed \(v\) in the \(x-y\) plane as shown in the figure Which of the following statement is false for the angular momentum \(\vec L\) about the origin ?

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) Both (b) and (c)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{L}}=\overrightarrow{\mathrm{r}} \times \overrightarrow{\mathrm{P}}\) or \(\overrightarrow{\mathrm{L}}=\mathrm{rpsin} \theta \hat{\mathrm{n}}\)
\(\overrightarrow{\mathrm{L}}=\mathrm{r}_{\perp}(\mathrm{P}) \hat{\mathrm{n}}\)
For \(D\) to \(A\)
\(\overrightarrow{\mathrm{L}}=\frac{\mathrm{R}}{\sqrt{2}} \mathrm{mV}(-\hat{\mathrm{k}})\)
For \(A\) to \(B\)
\(\overrightarrow{\mathrm{L}}=\frac{\mathrm{R}}{\sqrt{2}} \mathrm{mV}(-\hat{\mathrm{k}})\)
For \(\mathrm{C}\) to \(\mathrm{D}\)
\(\overrightarrow{\mathrm{L}}=\left(\frac{\mathrm{R}}{\sqrt{2}}+\mathrm{a}\right) \mathrm{mV}(\hat{\mathrm{k}})\)
For \(B\) to \(C\)
\(\overrightarrow{\mathrm{L}}=\left(\frac{\mathrm{R}}{\sqrt{2}}+\mathrm{a}\right) \mathrm{mV}(\hat{\mathrm{k}})\)
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