JEE Mains · Physics · STD 11 - 2. motion in straight line
A ball is thrown vertically upward with an initial velocity of \(150\,m / s\). The ratio of velocity after \(3\,s\) and \(5\,s\) is \(\frac{x+1}{x}\). The value of \(x\) is \(...........\) Take \(\left(g=10\,m / s ^2\right)\)
- A \(6\)
- B \(5\)
- C \(-5\)
- D \(10\)
Answer & Solution
Correct Answer
(B) \(5\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ V }=\overrightarrow{ u }+\overrightarrow{ a t}\) \(V =150-10 t\) \(V (3)=150-30=120\) \(V (5)=150-50=100\) \(\frac{120}{100}=\frac{ x +1}{ x }=\frac{6}{5} \Rightarrow x =5\)
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