ইঞ্জিনিয়ারিং মেকানিক্স MCQ
1. In a screw jack an effort of 50kg is required to lift a load of 100kg. The mechanical advantage of the machine is-
5
4
3
2
2. The shortest distance measured along the normal to the helix between corresponding points on the adjacent teeth is called-
Gear pitch
Helical pitch
Circular pitch
Normal circular pitch
3. The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of-
Friction
limiting friction
Repose
kinematic friction
4. The distance between the corresponding points on adjacent teeth measured on the pitch circle is-
Helical pitch
Normal pitch
Gear pitch
Circular pitch
5. In the equation of virtual work, following force is neglected-
reaction of any smooth surface with which the body is in contact
reaction of a rough surface of a body which rolls on it without slipping
reaction at a point or an axis, fixed in space, around which a body is con-strained to turn
all of the above
6. The angle at which the teeth of the gear are inclined to the axis of a gear is called as-
Pitch angle
Normal angle
Helix angle
Gear angle
7. A sample of metal weighs 219 gms in air, 180 gms in water, 120 gms in an unknown fluid. Then which is correct statement about density of metal-
density of metal can't be determined
metal is twice as dense as water
metal will float in water
metal is twice as dense as unknown fluid
8. Which gears are used to connect two intersecting shaft axes?
Crossed helical gear
Worm and worm wheel
Bevel gears
All of the above
9. The contract ratio of a gear is
Zero
less than
More than 1
Infinite
10. Determine torque transmitted on the pinion shaft if torque transmitted on gear shaft is 20 N.m. Consider Gear ratio = 4
8 N-m
5 N-m
80 N-m
16 N-m
11. Which of the following is the example of lever of first order?
arm of man
pair of scissors
pair of clinical tongs
all of the above
12. When a body of mass m attains a velocity v from rest in time I then kinetic energy of translation is-
mv²
mgv²
0.5v²
0.5mv ²
13. A stone is dropped from rest from a height 'h' meter, it takes four seconds to reach the ground, the height 'h' is-
70.5
78.4
80.6
98
14. Two spiral gears have a normal module of 10mm and the angle between the skew shaft axes is 50°. The driver has 20 teeth and the helix angle of it is 30°. If the velocity ratio is 1/3 and the driver as well as the follower are both left handed, find the centre distance between the shafts.
434.72mm
452.83mm
582.19mm
523.39mm
15. A framed structure is perfect if it contains members equal to-
2n-3
n-1
2n-1
n-2
16. D' Alembert's principle is used for-
reducing the problem of kinetics to equivalen statics problenz
determining stresses in the truss
stability of floating bodies
designing safe structures
17. The force applied on a body of mass 100kg to produce an acceleration 5m/s² in-
20 N
100 N
500 N
None
18. An object travels along a path, the equatiorr of distance 'x' travelled in time 't' is given by x = t²(2t+4), acceleration of the object at zero time in appropriate unit is-
4
6
8
12
19. What is meant by gear ratio?
The ratio of pinion speed and gear speed
The ratio of number of teeth on pinion and number of teeth on gear
Both ক. and খ.
None of the above
20. The possible loading in various members of framed structures are-
compression or tension
bucking or shear
shear or tension
all of the above