WBJEE · Physics · Laws of Motion
A box of mass \(2 \mathrm{kg}\) is placed on the roof of a car. The box would remain stationary until the car attains a maximum acceleration. Coefficient of static friction between the box and the roof of the car is 0.2 and \(g=10 \mathrm{ms}^{-2}\) This maximum acceleration of the car, for the box to remain stationary, is
- A \(8 \mathrm{ms}^{-2}\)
- B \(6 \mathrm{ms}^{-2}\)
- C \(4 \mathrm{ms}^{-2}\)
- D \(2 \mathrm{ms}^{-2}\)
Answer & Solution
Correct Answer
(D) \(2 \mathrm{ms}^{-2}\)
Step-by-step Solution
Detailed explanation
Given, \(m=2 \mathrm{kg}, \mu=0.2\) and \(g=10 \mathrm{ms}^{-2}\) Here, \(\quad m a=\mu m g\) \[ \begin{array}{l} a=\mu g \\ a=0.2 \times 10 \\ a=2 \mathrm{m} / \mathrm{s}^{2} \end{array} \]
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