The connecting rod of a vertical reciprocating engine is \(2 \mathrm{~m}\) long between centres and its mass is \(250 \mathrm{~kg}\). The mass centre is \(750 \mathrm{~mm}\) from the big end bearing. When suspended as a pendulum from the gudgeon pin axis, it makes 10 complete oscillations in 25 seconds. Calculate the radius of gyration of the rod about an axis through its mass centre. The crank is \(400 \mathrm{~mm}\) long and rotates at \(250 \mathrm{rpm}\).

When the crank has turned through \(35^{\circ}\) from the TDC and the piston is moving downwards, find the inertia torque exerted on the crankshaft.