2D/(D - d)
D/(D + d)
2D/(D + d)
D/(D - d)

Engineering Mechanics Which of the following statement is incorrect?

The velocity ratio of a machine is the ratio of load lifted to the effort applied
A machine whose efficiency is 100% is known as an ideal machine
A force acting in the opposite direction to the motion of the body is called force of friction
The ratio of the limiting friction to the normal reaction is called coefficient of friction

Engineering Mechanics The motion of a wheel of a car is

None of the listed here
Purely translation
Combined translation and rotational
Purely rotational

Engineering Mechanics Two forces are acting at an angle of 120°. The bigger force is 40 N and the resultant is perpendicular to the smaller one. The smaller force is

40 N
20 N
None of the listed here
120 N

Engineering Mechanics The term 'Centroid' is

None of the listed here
The same as centre of gravity
The point of suspension
The point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis