Mechanical Engineering Answers

At what stage the sheet metal is called as pattern???

The diagonal angle in scoop making layout

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A prop shaft of a heavy-duty truck has two bearings which are positioned at 3 metres from each other. The shaft must rotate at 30 rad/s when the truck travels at the speed of 40 m/s. Such a shaft carries two masses of (MA = 10 kg) and (MB = 5 kg) acting at the extremities of the arms 0.45 m and 0.6 m long, respectively. The planes in which these masses rotate are 1.2 m and 2.4 m,

respectively, from the left end bearing supporting the shaft. The angle between the arms is 60°. If the masses are balanced by two counter-masses (named X and Y) rotating with the shaft acting at a radius of 0.3 m and placed at 0.3 m from each bearing centre:

• Draw a diagram illustrating the position of masses on the shaft.
• Calculate the dynamic force in Newtons. Tabulate the results.
• Calculate the moment acting on the shaft in Newton-metre. Tabulate the results.
• Determine the magnitude of the Y balance mass using a vector diagram.
• Determine the magnitude of the X balance mass using a vector diagram.

An inward flow reaction turbine is required to produce a power of 280 kW at 200

rpm. The effective head on the turbine is 20 m. The inlet diameter is twice as the

outlet diameter. Assume hydraulic efficiency as 80%. The radial

velocity is 3.5 m/s and is constant. The ratio of breadth to wheel diameter is 0.1

and 5% of the flow area is blocked by vane thickness. Determine the inlet and

outlet diameters, inlet and exit vane angle and guide blade angle at the inlet.

Assume radial discharge.

A lorry with mass 3500 kg is parked at the top of a steep hill with a 1– in– 8 gradient when its handbrake fails. Assume that the lorry has a constant frictional resistance to motion of 500 N. The lorry rolls 40 m down the hill before crashing into a lamp post. Use the principle of conservation of energy to calculate the velocity of the lorry immediately prior to its impact with the lamp post.

A lift cage with mass 500 kg accelerates vertically upwards from rest to a velocity of 6 m s −1 in a distance of 12 m. The frictional resistance to motion is assumed to be constant throughout at 200 N. a) Calculate the work done raising the lift. b) Calculate the tension in the lifting cable. c) Calculate the power developed by the winch. A lorry with mass 3500 kg is parked at the top of a steep hill with a 1– in– 8 gradient when its handbrake fails. Assume that the lorry has a constant frictional resistance to motion of 500 N. The lorry rolls 40 m down the hill before crashing into a lamp post. Use the principle of conservation of energy to calculate the velocity of the lorry immediately prior to its impact with the lamp post.

A satellite launch vehicle travelling at 1000 m s −1 uses a controlled explosion to release its payload into orbit. The empty launch vehicle has a mass of 7500 kg and the satellite released has mass 250 kg. Both continue travelling in the same direction, with the launch vehicle now moving at 900 m s −1 . a) Calculate the initial momentum of the launch vehicle immediately before the satellite was released. b) Calculate the final velocity of the satellite after release.

During a particular the specific heat of the working fluid comprising system is given by the relation: (C=0.2 + 0.002 T) kj/kg K. where T is the absolute temperature in degree Kelvin. What amount of the heat is required to be supplied to the fluid system to raise it's temperature from 300 K to 400K? Also determine the me mean value of specific heat.

The pressure on 142 l/min of air is boosted reversibly from 2,068.44 kPaa to 6,205.32 kPaa while the temperature remains constant at 24° C ∆U= 0. a) find the integral of pdV and - integral of Vdp. (b) for a nonflow process, find W,Q,∆H, and ∆S. (c) for steady flow process during which ∆K= 5 kJ/min and ∆P=0, find the integral of pdV, - integral of Vdp, W, ∆E, ∆H, Q, and ∆S

The bars AB and AC are joined by a pin at A and a horizontal cable. The vertical cable carrying the 200-kg mass is attached to the pin at A. Determine the tension in the horizontal cable. Neglect the weights of the bars.

Determine the tension in horizontal cable in N