SECTION-1

# ENGINEERING MECHANICS MCQ

**Q51:- Which is the correct statement about law of polygon of forces?**

(a) If any number of forces acting at a point can be represented by the sides of a polygon taken in order, then the forces are in equilibrium

(b) If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon, then the forces are in equilibrium

(c) If a polygon representing forces acting at a point is closed then forces are in equilibrium

(d) If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon taken in order, then the forces are in equilibrium

**Q52:- The forces, which meet at one point and their lines of action also lie on the same plane, are known as**

(a) Coplanar concurrent forces

(b) Coplanar non-concurrent forces

(c) Non-coplanar concurrent forces

(d) Non-coplanar non-concurrent forces

**Q53:- Three forces acting on a rigid body are represented in magnitude, direction and line of action by the three sides of a triangle taken in order. The forces are equivalent to a couple whose moment is equal to**

(a) Area of the triangle

(b) Twice the area of the triangle

(c) Half the area of the triangle

(d) None of these

**Q54:- The Cartesian equation of trajectory is (where u = Velocity of projection, α = Angle of projection, and x, y = Co-ordinates of any point on the trajectory after t seconds.)**

(a) y = (gx²/2u² cos²α) + x. tanα

(b) y = (gx²/2u² cos²α) – x. tanα

(c) y = x. tanα – (gx²/2u² cos²α)

(d) y = x. tanα + (gx²/2u² cos²α)

**Q55:- Centre of gravity of a solid cone lies on the axis at the height**

(a) One fourth of the total height above base

(b) One third of the total height above base

(c) One-half of the total height above base

(d) Three eighth of the total height above the base

**Q56:- The term ‘Centroid’ is**

(a) The same as centre of gravity

(b) The point of suspension

(c) The point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis

(d) None of the above

**Q57:- The skidding away of the vehicle on a level circular path can be avoided if the force of friction between the wheels and the ground is __________ the centrifugal force.**

(a) Less than

(b) Greater than

(c) Equal to

(d) None of these

**Q58:- A spherical body is symmetrical about its perpendicular axis. According to Routh’s rule, the moment of inertia of a body about an axis passing through its centre of gravity is (where, M = Mass of the body, and S = Sum of the squares of the two semi-axes.)**

(a) MS/3

(b) MS/4

(c) MS/5

(d) None of these

**Q59:- Non-coplanar non-concurrent forces are those forces which**

(a) Meet at one point, but their lines of action do not lie on the same plane

(b) Do not meet at one point and their lines of action do not lie on the same plane

(c) Do not meet at one point but their lines of action lie on the same plane

(d) None of the above

**Q60:- Moment of inertia of a circular section about its diameter (d) is**

(a) πd3/16

(b) πd3/32

(c) πd4/32

(d) πd4/64

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**Read More Sections of Engineering Mechanics**

Each section contains maximum 80 Questions. To practice more questions visit other sections.

**Engineering Mechanics Objective Questions – Section-1**

**Engineering Mechanics Objective Questions – Section-2**

**Engineering Mechanics Objective Questions – Section-3**

**Engineering Mechanics Objective Questions – Section-4**

**Engineering Mechanics Objective Questions – Section-5**