A metallic bar having uniform area of cross-section having length \(0.8\) and mass \(4kg\) is supported on two knife edge placed at \(10cm\) from each end of bar. A \(6.0kg\) load is suspended at \(30cm\) from left end of the bar. How much is the reaction at the knife edges? Take: \(g=10\frac{m}{s^{2}}\).
Ans: \(R_{1}=65N\) and \(R_{2}=35N\).
A bus of mass \(12000kg\) is standing on a horizontal road. The distance between the front and rear axle is \(1.5m\). The centre of gravity of the bus is at \(1.0m\) behind the front axle. how much is the force exerted by the ground on each front and rear wheel?
Ans: \(F_{1}=\left(3.92\times10^{4}\right)N\) and \(F_{2}=\left(7.8\times10^{4}\right)N\).
A metre rule is balanced on a knife edge at its centre. When two coins each of mass \(5g\) are put on top of the other at the \(12cm\) mark, the stick is found to be balanced at \(45.0cm\). calculate: the mass of the metre rule.
Ans: \(M=66g\).
A uniform rod of length \(2m\) having mass \(2kg\) rests against a smooth wall at an angle of \(30^{o}\) with the ground. Calculate: the force exerted by ground on the road.
