Engineering Mechanics MCQs

Question 1

The units of moment of inertia of an area are

Accepted Answer

m4

Answer

kg-m2

Answer

kg/m2

Answer

m3

Question 2

A pair of smith's tongs is an example of the lever of

Accepted Answer

First order

Answer

Zeroth order

Answer

Second order

Answer

Third order

Question 3

The centre of gravity of an isosceles triangle with base (p) and sides (q) from its base is

Accepted Answer

$$\frac{{\sqrt {4{{	ext{p}}^2} - {{	ext{q}}^2}} }}{6}$$

Answer

$$\frac{{4{{	ext{p}}^2} - {{	ext{q}}^2}}}{6}$$

Answer

$$\frac{{{{	ext{p}}^2} - {{	ext{q}}^2}}}{4}$$

Answer

$$\frac{{{{	ext{p}}^2} + {{	ext{q}}^2}}}{4}$$

Question 4

The point, through which the whole weight of the body acts, irrespective of its position, is known as

Accepted Answer

Center of gravity

Answer

Moment of inertia

Answer

Center of percussion

Answer

Center of mass

Question 5

The resultant of the two forces ‘P’ and ‘Q’ is ‘R’. If ‘Q’ is doubled, the new resultant is perpendicular to ‘P’. Then

Accepted Answer

Q = R

Answer

P = Q

Answer

Q = 2R

Answer

None of these

Question 6

The moment of the force ‘P’ about ‘O’ as shown in the below figure is

Accepted Answer

P × OC

Answer

P × OA

Answer

P × OB

Answer

P × AC

Question 7

The total momentum of a system of masses (i. e. moving bodies) in any one direction remains constant, unless acted upon by an external force in that direction. This statement is called

Accepted Answer

Principle of conservation of momentum

Answer

Newton's first law of motion

Answer

Newton's second law of motion

Answer

Principle of conservation of energy

Question 8

The unit of force in S.I. system of units is

Accepted Answer

Newton

Answer

Dyne

Answer

Kilogram

Answer

Watt

Question 9

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

Accepted Answer

$${	ext{y}} = {	ext{x}}	an \alpha - \frac{{{	ext{g}}{{	ext{x}}^2}}}{{2{{	ext{u}}^2}{{\cos }^2}\alpha }}$$

Answer

$${	ext{y}} = \frac{{{	ext{g}}{{	ext{x}}^2}}}{{2{{	ext{u}}^2}{{\cos }^2}\alpha }} + {	ext{x}}	an \alpha $$

Answer

$${	ext{y}} = \frac{{{	ext{g}}{{	ext{x}}^2}}}{{2{{	ext{u}}^2}{{\cos }^2}\alpha }} - {	ext{x}}	an \alpha $$

Answer

$${	ext{y}} = {	ext{x}}	an \alpha + \frac{{{	ext{g}}{{	ext{x}}^2}}}{{2{{	ext{u}}^2}{{\cos }^2}\alpha }}$$