Engineering Mechanics MCQs

Question 1

The moment of inertia of a solid cone of mass ‘m’ and base radius ‘r’ about its vertical axis is

Accepted Answer

$$\frac{{3{	ext{m}}{{	ext{r}}^2}}}{{10}}$$

Answer

$$\frac{{3{	ext{m}}{{	ext{r}}^2}}}{5}$$

Answer

$$\frac{{2{	ext{m}}{{	ext{r}}^2}}}{5}$$

Answer

$$\frac{{4{	ext{m}}{{	ext{r}}^2}}}{5}$$

Question 2

A redundant frame is also called __________ frame.

Accepted Answer

Imperfect

Answer

Perfect

Answer

Deficient

Answer

None of these

Question 3

The horizontal range of a projectile (R) is given by

Accepted Answer

$${	ext{R}} = \frac{{{{	ext{u}}^2}\sin2\alpha }}{{	ext{g}}}$$

Answer

$${	ext{R}} = \frac{{{{	ext{u}}^2}\cos 2\alpha }}{{	ext{g}}}$$

Answer

$${	ext{R}} = \frac{{{{	ext{u}}^2}\cos \alpha }}{{	ext{g}}}$$

Answer

$${	ext{R}} = \frac{{{{	ext{u}}^2}\sin\alpha }}{{	ext{g}}}$$

Question 4

If the body falls freely under gravity, then the gravitational acceleration is taken as

Accepted Answer

+9.8 m/s2

Answer

+8.9 m/s2

Answer

-8.9 m/s2

Answer

-9.8 m/s2

Question 5

The velocity ratio of a single purchase crab winch can be increased by

Accepted Answer

Increasing the length of the handle

Answer

Increasing the radius of the load drum

Answer

Increasing the number of teeth of the pinion

Answer

All of the above

Question 6

Concurrent forces are those forces whose lines of action

Accepted Answer

Meet at one point

Answer

Lie on the same line

Answer

Meet on the same plane

Answer

None of these

Question 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

Accepted Answer

Density of metal can't be determined

Answer

Metal is twice as dense as water

Answer

Metal will float in water

Answer

Metal is twice as dense as unknown fluid

Question 8

The center of percussion of a solid cylinder of radius ‘r’ resting on a horizontal plane will be

Accepted Answer

$$\frac{{3{	ext{r}}}}{2}$$

Answer

$$\frac{{	ext{r}}}{2}$$

Answer

$$\frac{{2{	ext{r}}}}{3}$$

Answer

$$\frac{{	ext{r}}}{{	ext{A}}}$$

Question 9

The magnitude of two forces, which when acting at right angle produce resultant force of $$\sqrt {10} $$ kg and when acting at 60° produce resultant of $$\sqrt {13} $$ kg. These forces are

Accepted Answer

$$\sqrt 5 $$ and $$\sqrt 5 $$

Answer

2 and $$\sqrt 6 $$

Answer

3 and 1 kg

Answer

2 and 5