Machine Design MCQs

Question 1

Which of the following pipe joints would be suitable for pipes carrying steam?

Accepted Answer

Expansion

Answer

Flanged

Answer

Threaded

Answer

Bell and spigot

Question 2

The expression 0.175 - 0.841/T is the Lewis form factor for

Accepted Answer

20° stub system

Answer

$$14{\frac{1}{2}^ \circ }$$ composite and full depth involute system

Answer

20° full depth involute system

Answer

None of the above

Question 3

In worm gears, the pressure angle is __________ the angle between two inclined faces in axial plane.

Accepted Answer

Half

Answer

Twice

Answer

Thrice

Answer

None of these

Question 4

The ultimate strength of steel in tension in comparison to shear is in the ratio of

Accepted Answer

3 : 2

Answer

1 : 1

Answer

2 : 1

Answer

2 : 3

Question 5

According to maximum normal stress theory, the maximum normal stress in the shaft is

Accepted Answer

$$\frac{1}{2}\left( {\sigma + \sqrt {{\sigma ^2} 	imes 4{	au ^2}} } ight)$$

Answer

$$\frac{1}{2}\sqrt {{\sigma ^2} 	imes 4{	au ^2}} $$

Answer

$$\sqrt {{\sigma ^2} 	imes 4{	au ^2}} $$

Answer

$$\sigma + \sqrt {{\sigma ^2} 	imes 4{	au ^2}} $$

Question 6

When a circular beam of diameter d is subjected to a shear force F, the maximum shear stress induced will be

Accepted Answer

$$\frac{{{	ext{16F}}}}{{3\pi {{	ext{d}}^2}}}$$

Answer

$$\frac{{4{	ext{F}}}}{{\pi {{	ext{d}}^2}}}$$

Answer

$$\frac{{{	ext{6F}}}}{{\pi {{	ext{d}}^2}}}$$

Answer

$$\frac{{{	ext{8F}}}}{{\pi {{	ext{d}}^2}}}$$

Question 7

When a beam of rectangular cross-section of width b and depth d, is subjected to a shear force F, the maximum shear stress induced will be

Accepted Answer

$$\frac{{{	ext{3F}}}}{{{	ext{2bh}}}}$$

Answer

$$\frac{{	ext{F}}}{{{	ext{bh}}}}$$

Answer

$$\frac{{{	ext{2F}}}}{{{	ext{bh}}}}$$

Answer

$$\frac{{{	ext{4F}}}}{{{	ext{bh}}}}$$

Question 8

The wire ropes make contact at

Accepted Answer

Bottom of groove of the pulley

Answer

Sides and bottom of groove of the pulley

Answer

Anywhere in the groove of the pulley

Answer

Sides of groove of the pulley

Question 9

Stress concentration in cyclic loading is more serious in

Accepted Answer

Ductile materials

Answer

Brittle materials

Answer

Equally serious in both cases

Answer

Depends on other factors