Engineering Mechanics MCQs

Question 1

A weight of 1000 N can be lifted by an effort of 80 N. If the velocity ratio is 20, the machine is

Accepted Answer

Reversible

Answer

Non-reversible

Answer

Ideal

Answer

None of these

Question 2

A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will act

Accepted Answer

Zero at its upper end

Answer

Downward at its upper end

Answer

Upward at its upper end

Answer

Perpendicular to the wall at its upper end

Question 3

A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act

Accepted Answer

Upward at its upper end

Answer

Towards the wall at its upper end

Answer

Away from the wall at its upper end

Answer

Downward at its upper end

Question 4

The moment of inertia of a rectangular section 3 cm wide and 4 cm deep about X-X axis is

Accepted Answer

16 cm4

Answer

9 cm4

Answer

12 cm4

Answer

20 cm4

Question 5

The product of either force of couple with the arm of the couple is called

Accepted Answer

Moment of the couple

Answer

Resultant couple

Answer

Moment of the forces

Answer

Resulting couple

Question 6

The resolved part of the resultant of two forces inclined at an angle 'θ' in a given direction is equal to

Accepted Answer

The algebraic sum of the resolved parts of the forces in the given direction

Answer

The sum of the resolved parts of the forces in the given direction

Answer

The difference of the forces multiplied by the cosine of θ

Answer

The sum of the forces multiplied by the sine of θ

Question 7

One end of a helical spring is fixed while the other end carries the load W which moves with simple harmonic motion. The frequency of motion is given by (where $$\delta $$ = Deflection of the spring.)

Accepted Answer

$$\frac{1}{{2\pi }}\sqrt {\frac{g}{\delta }} $$

Answer

$$2\pi \sqrt {\frac{g}{\delta }} $$

Answer

$$2\pi \sqrt {\frac{\delta }{g}} $$

Answer

$$\frac{1}{{2\pi }}\sqrt {\frac{\delta }{g}} $$

Question 8

The moment of inertia of a sphere of mass 'm' and radius 'r', about an axis tangential to it, is

Accepted Answer

$$\frac{7}{5}{	ext{m}}{{	ext{r}}^2}$$

Answer

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

Answer

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

Answer

$$\frac{7}{3}{	ext{m}}{{	ext{r}}^2}$$

Question 9

If the masses of both the bodies, as shown in the below figure, are reduced to 50 percent, then tension in the string will be

Accepted Answer

Half

Answer

Same

Answer

Double

Answer

None of these