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Q2. our wheels each of mass 400 kg, diameter 0.5 m and radius of gyration 0.2 m. It is travelling at 2 m/s when it starts to descend an incline of 4°. The incline is 180 m long and resistance to motion is constant at 900 N. Calculate EACH of the following:

(a) the energy lost in descending the incline;

(b) the speed of the truck at the bottom of the incline.

Q1. A vertical post and horizontal tie support a loaded jib as shown in Fig Q2. The load of 40 kN is suspended on a load wire which is allowed to oscillate through 60 degrees.

Calculate EACH of the following:

(a) the maximum force on the jib allowing for the centrifugal load;

(b) the tension in the load wire at the point of its nearest approach to the jib.

Q3. When a two - ram hydraulic steering gear has the rudder at an angle of 30°, the hydraulic oil pressure is 60 bar and the rudder is moving at 0.033 rad/sec. The rams are 220 mm diameter and the distance between the centreline of the rams and the centre of the rudder stock is 1.1 m.

Calculate EACH of the following:

(a) the power delivered to the rudder stock;

(b) the bending moment in the tiller arm at a point 700 mm from the centre of the rudder stock.

Q1. A centrifugal clutch is shown in Fig Q4 and has four shoes retained by springs. The shoes first contact the output drum at 9 rev/s, at which point the centre of gravity of each shoe is at a radius of 120 mm from the shaft axis. The internal radius of the output drum is 150 mm. When the drive shaft speed is then increased to 15 rev/s, the maximum power transmitted to the output shaft is 30 kW.

Calculate the mass of each shoe if the coefficient of friction between the shoes and the drum is 0.5.

Fig

Q1. A centrifugal pump delivers 900 tonne of sea water per hour. The impeller has an inlet width of 80 mm and an exit diameter of 440 mm. When running at 720 rev/min the radial flow velocity of the water is constant at 3.2 m/sec and the absolute velocity at exit is 9 m/sec.

Calculate EACH of the following:

(a) The impeller diameter at inlet;

(b) The inlet angle of the impeller vanes for shock-less flow;

(c) The exit angle of the impeller vanes for shock-less flow.

Note: Density of sea water = 1025 kg/m³.