41. The radius of gyration is the distance where the whole mass (or area) of a body is assumed to be concentrated.
Correct
Incorrect
✅ The correct answer is option A.
Engineering Mechanics MCQs
43. The law of the machine is(where P = Effort applied to lift the load, m = A constant which is equal to the slope of the line, W = Load lifted, and C = Another constant which represents the machine friction.)
P = mW – C
P = m/W + C
P = mW + C
P = C – mW
✅ The correct answer is option C.
44. If the number of pulleys in a system is equal to its velocity ratio, then it is a __________ system of pulleys
first
second
third
✅ The correct answer is option B.
45. If three forces acting at a point be represented in magnitude and direction by the three sides of a triangle, taken in order, the forces shall be in equilibrium.
TRUE
FALSE
✅ The correct answer is option A.
46. When the spring of a watch is wound, it will possess
strain energy
kinetic energy
heat energy
electrical energy
✅ The correct answer is option A.
47. A machine having an efficiency less than 50%, is known as
reversible machine
non-reversible machine
neither reversible nor non-reversible machine
ideal machine
✅ The correct answer is option B.
48. The centre of oscillation and centre of suspension for a compound pendulum are interchangeable.
TRUE
FALSE
✅ The correct answer is option A.
49. A block ot mass 20 kg lying on a rough horizontal plane is connected by a light string passing over a smooth pulley to another mass 5 kg, which can move freely in the Vertical direction, as shown in the below figure. The tension in the string will __________ with the increase in coefficient of friction.
increase
decrease
not be effected
✅ The correct answer is option A.
50. A screw jack used for lifting the loads is
a reversible machine
a non-reversible machine
an ideal machine
none of these
✅ The correct answer is option B.