JEE Mains · Physics · STD 11 - 4.1 newtons laws of motion
A body of mass \(2\, kg\) moves under a force of \((2 \hat{ i }+3 \hat{ j }+5 \hat{ k }) \,N\). It starts from rest and was at the origin initially. After \(4 \,s\), its new coordinates are \((8, b, 20)\). The value of \(b\) is ........ . (Round off to the Nearest Integer)
- A \(16\)
- B \(8\)
- C \(12\)
- D \(20\)
Answer & Solution
Correct Answer
(C) \(12\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ a } =\frac{\overrightarrow{ F }}{ m }=\frac{2 \hat{ i }+3 \hat{ j }+5 \hat{ k }}{2}\) \(=\hat{ i }+1.5 \hat{ j }+2.5 \hat{ k }\) \(\vec{r} =\overrightarrow{ u } t +\frac{1}{2} \overrightarrow{ a } t ^{2}\)…
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