A particle of mass 40 kg is kept on a smooth plane inclined at an angle of 30º to the horizontal by a force up the plane. find, correct to one decimal place, the magnitude of the normal reaction of the plane of the particle.[Take g = 10 ms\(^{-2}\)]
- 146.0N
- 200.6N
-
346.4N
- 400.3N
The correct answer is: C
Explanation
Weight of particles = mass x accel. due to gravity
W = m g = 40 x 10 = 400N
The weight can be resolved into the x and y components.
Since we are calculating for normal reaction, we use the y component
W\(_y\) = W cos\(\theta\) = 400 Cos 30 = 400 x \(\frac{\sqrt{3}}{2}\) = 200 x \(\sqrt{3}\) = 346.4N