JEE Mains · Physics · STD 11 - 2. motion in straight line
If \(t =\sqrt{ x }+4\), then \(\left(\frac{ dx }{ dt }\right)_{ t =4}\) is.
- A \(4\)
- B \(0\)
- C \(8\)
- D \(16\)
Answer & Solution
Correct Answer
(B) \(0\)
Step-by-step Solution
Detailed explanation
\(t =\sqrt{ x }+4\) \(\Rightarrow x =( t -4)^{2}= t ^{2}-8 t +16\) \(\Rightarrow \frac{ dx }{ dt }=2 t -8\) \(\left.\Rightarrow \frac{ dx }{ dt }\right|_{ t =4}=2 \times 4-8=0\)
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