Theory of Machi...

What are the minimum number of kinematic pairs required in a kinematic chain?

A 20° gear set has an addendum of 12mm and a module of 8mm. If the pinion has 20 teeth and the gear has 36 teeth, then the center distance is __________m. (round up to two decimals)

Which of the following is NOT a flexible link?

A four-bar mechanism is as shown in the figure below. At the instant shown, AB is shorter than CD by 30 cm. AB is rotating at 5 rad/sec and CD is rotating at 2 rad/sec.

The length of AB is

In a 20˚ full depth involute gear system, centre distance between pinion and gear is 120 mm. If module of gear is 4 mm and number of teeth is 40, then number of teeth on pinion is___

The minimum number of links in a single degree-of-freedom planar mechanism with both higher and lower kinematic pairs is:

If angle of obliquity of pair of gear wheels is 18˚. What is minimum number of teeth on pinion if arc of approach or recess not less than the pitch?

A flywheel has moment of inertia of 11.8 kg-m². What is the maximum fluctuation of speed of the flywheel for a fluctuation energy of 2049 joules? The mean speed of the flywheel is 180 rpm.

A planar mechanism has 8 links and 10 rotary joints. The number of degrees of freedom of the mechanism, using Grubler's criterion, is

In case of rotating masses, the magnitude of the balancing mass is ______ when the speed of the shaft is doubled.

The number degrees of freedom of a planar linkage with 8 links and 9 simple revolute joints is

Mechanism which has more than four links is:

The number of inversions for a slider crank mechanism is

A simple quick return mechanism is shown in the figure. The forward to return ratio of the quick return mechanism is 2: 1. If the radius of the crank O1P is 125 mm, then the distance 'd' (in mm) between the crank centre to lever pivot centre point should be

Find velocity of slider (cm/sec) as shown in figure. (Link CD and DE is connected through a rigid part and should consider a single link)

AB = 10 cm, BC = 25 cm, CD = 30 cm, DE = 20 cm and EF = 40 cm

An aeroplane makes a complete half circle of 50 metres radius, towards left, when flying at 50 m/s. The rotary engine and the propeller of the plane has a mass of 400 kg and a radius of gyration of 0.3 m. The engine rotates at 2400 r.p.m. clockwise when viewed from the rear. Find the gyroscopic couple on the aircraft (in kN.m)

In a 4 bar mechanism shown in figure, what is angular velocity of link BC and DC? If angular velocity on input link AB is 2 rad/s.

In a four-bar linkage, S denotes the shortest link length, L is the longest link length, P and Q are the lengths of other two links. At least one of the three moving links will rotate by 360° if

The lengths of the links of a 4-bar linkage with revolute pairs only are p, q, r, and s Given that p < q < r < s. Which of these links should be the fixed one, for obtaining a “double crank” mechanism?

The equation of the turning moment diagram for the three crank engine is given by: (T(N-m) = 25000 - 7500 sin 3θ) where θ radians is the crank angle from inner dead centre. The moment of inertia of the flywheel is 400 kg-m² and the mean engine speed is 300 rpm. Calculate the power of the engine.

In a cam-follower, the follower rises by 80 mm as the cam rotates 0.3 radians at constant angular velocity of 6 rad/sec. The follower is uniformly accelerating during the first half and it is uniformly decelerating in the later half. Assuming the same magnitudes of the acceleration and deceleration, the maximum velocity of the follower in m/s is________?

Choose the option which does NOT belong to the category of simple machine:

The input link O₂P of a four bar linkage is rotated at 2 rad/s in counter clockwise direction as shown below. The angular velocity of the coupler PQ in rad/s, at an instant when ∠O₄O₂ P = 180°, is

Beam engine mechanism is an example of

A flywheel of 160 kg.m² is used to control the speed fluctuation in an electric shaper machine. The machine uses a motor which supplies the power at a uniform rate of 1.2 kW. The crank of the shaper runs at 20 rpm and the quick return ratio is 2. Assuming that power is required only during the cutting stroke calculate the fluctuation of speed of flywheel as a percentage of the mean speed of 240 rpm.