GATE 2021 ME : Toppers Quiz 34 (App update required to attempt this test) for ESE & GATE ME Exams

Question 1

Liquid sodium is to be heated from 128 ºC to 149 ºC at a rate of 2.7kg/sec in 28mm tube at constant heat flux. Calculate minimum length of the tube if wall temperature does not exceed 185 ºC. (Properties of sodium, at 138.5 ºC: ƿ= 916kg/m³ , pr= 0.089, kinematic viscosity=0.185×10^-6 m²/s, C_p= 1.5678kJ/kg-ºC, k= 86.7W/m-ºC.
Assume Nu= 4.82+0.0185

Where pe = peclet number

Question 2

A circular shaft subjected to twisting moment result in maximum shear stress of 50 MPa. Then the maximum compressive stress in the material is

Question 3

A simple mechanism with all link constrained to move in one direction only has 5 links, another mechanism with similar configuration has 6 links. What is the ratio of number of instantaneous centre of the two mechanisms?

Question 4

The average heat produced by oranges ripening is estimated to be 300 W/m2. Taking the average size of an orange to be 8 cm and assuming it to be a sphere with k = 0.15 W/m-K, the temperature at the centre of orange when outer surface is maintained at 10 °C is

Question 5

A column (E= 200GPa) fixed on both ends, its height is 1m and cross-section is 15mm×30mm. Critical buckling load in kN which the column withstands____________

Question 6

Find efficiency of reheat cycle as shown below. Pump work is 20 kJ/kg and steam flow rate is 2 kg/s. Find efficiency of the cycle.

Question 7

Find the amount of work supplied by the engine (in kW) if fuel of Calorific Value 45 MJ burns at a rate of 3kg/min in an Air Standard Otto cycle of compression ratio 7.

Question 8

Match the curves labelled A, B, C and D in figure with the types of fluid and select the correct answer:

1) Bingham plastic fluid

2) Ideal fluid

3) Shear thickening fluid

4) Pseudoplastic

5)Thixotropic

Question 9

A banner hoarding having dimensions 2m*2m is kept vertical by a 5m long pillar. Air blowing at 5 m/s is striking directly to the banner. If the maximum moment the pillar can withstand is 100 Nm. To reduce the drag force holes need to be cut out from the hoarding with a punch of 10 cm diameter. If the air drag coefficient is 0.5, then the total number of holes need to be cut out are

Question 10

A jet of water of 20 mm in diameter impinges on a smooth curve vane at its centre on the concave side and deflected by 160

. The reaction of vane was 20 N when the discharge from jet was 2 litre/s. The ratio of theoretical to actual force of jet is

Question 11

In a Hartnell governor with the range of speed is zero, when the radius of rotation of mass of ball is 40 mm the downward spring force is 120 N and when the radius of rotation is 60 mm the downward spring force is (in N) ______________.

Question 12

The hole dimension is

mm and the shaft dimension is

mm.
The resulting assembly has______.

Question 13

A spur gear is designated as
Module = 2 mm
Tooth thickness = 4 mm
Tooth length = 12 mm
Face width = 24 mm
Beam strength = 1.5 MPa
The Lewis form factor is_______.

Question 14

A block is moving on a inclined plane making an angle 45 ° with the horizontal and the coefficient of friction is

. The force required to push up the inclined plane is 3 times the force required to just prevent it from sliding down. Then

is

Question 15

The 4 jobs A, B, C and D are processed on 5 machines and the processing time of jobs on different machines is shown in following table:

According to Johnson’s rule the optimal job sequence is

Question 16

A mixture of moist air contains 20% vapor by mass and is kept in an isolated and rigid container of volume 0.85m³. If the density of fluid is 3 Kg/m³ and density of gas is 0.6 Kg/m³. Find the mass of the mixture in Kg.

Question 17

In a parallel flow heat exchanger, the inside heat transfer coefficient is 180W/

outside heat transfer coefficient is 250W/

. If the fouling factor for both inside and outside wall is 0.003

. Then overall heat transfer coefficient for the system will be

Question 18

A 140 mm diameter billet is extruded to 70 mm, at the working temperature of 800ºC. The average flow stress of material is 350 MPa, the force required for extrusion (in MN) is _____

Question 19

The ratio of volumetric strain of a thin cylinder to that of a thin spherical shell having the same internal pressure, same material and same internal diameter and thickness of spherical is twice that of cylindrical is_____ [take poisson’s ratio = 0.4]

Question 20

A mass of 2000 kg is currently being lowered at a velocity of 2 m/s from the drum as shown in the figure. The mass moment of inertia of the drum is 150 kg-m². On applying the brake, the mass is brought to rest in a distance of 0.5 m. The energy absorbed by the brake (in kJ) is

Question 21

Determine the maximum swaying couple of a two cylinder locomotive. Consider the following parameters:
Mass of reciprocating parts per cylinder = 300 kg
Distance between cylinder centre lines = 0.55 m
Crank radius = 0.2 m
Radius of wheel=0.9m
Cranks are at angles = 90 °
If the velocity of hammer blow is 80km/h and take c = 0.75

Question 22

A simply supported circular beam of diameter 30 mm uniformly loaded over the length shows the maximum deflection at centre as 7.5 mm. The beam is now replaced with another circular beam of diameter 40mm. The deflection in the current beam is

Question 23

A body acted upon by three forces

and

is in equilibrium. If the magnitude of

is 750N. Then the ratio of forces

to

i.e.

is

Question 24

Flow separation in flow past a solid object is caused by

Question 25

An eight-speed drilling machine uses drill of diameter ranging from 6mm to 36mm where the cutting speed is 15m/min. The ratio of any two consecutive speeds is