Machine Design MCQs

Question 1

According to Indian standard specifications, a Grey cast iron designated by 'FG 200' means that the

Accepted Answer

Minimum tensile strength is 200 N/mm2

Answer

Carbon content is 2%

Answer

Maximum compressive strength is 200 N/mm2

Answer

Maximum shear strength is 200 N/mm2

Question 2

The designation M 33 × 2 of a bolt means

Accepted Answer

Metric threads of 33 mm outside diameter and 2 mm pitch

Answer

Metric threads of 33 numbers in 2 cm

Answer

Metric threads with cross-section of 33 mm

Answer

Bolt of 33 mm nominal diameter having 2 threads per cm

Question 3

A bolt of M 24 × 2 means that

Accepted Answer

The nominal diameter of bolt is 24 mm and pitch is 2 mm

Answer

The pitch of the thread is 24 mm and depth is 2 mm

Answer

Cross-sectional area of the threads is 24 mm2

Answer

The effective diameter of bolt is 24 mm and there are 2 threads per cm

Question 4

The velocity factor for ordinary cut gears operating at velocities up to 12.5 m/s is equal to

Accepted Answer

$$\frac{3}{{3 + {	ext{v}}}}$$

Answer

$$\frac{{0.75}}{{0.75 + \sqrt {	ext{v}} }}$$

Answer

$$\frac{{4.5}}{{4.5 + {	ext{v}}}}$$

Answer

$$\frac{6}{{6 + {	ext{v}}}}$$

Question 5

According to Indian standard specifications, plain carbon steel designated by 40 C8 contains carbon

Accepted Answer

0.35 to 0.45%

Answer

0.20 to 0.40%

Answer

0.40 to 0.60%

Answer

None of these

Question 6

A bolt

Accepted Answer

Has a head on one end and a nut fitted to the other

Answer

Has head at one end and other end fits into a tapped hole in the other part to be joined

Answer

Has both the ends threaded

Answer

Is provided with pointed threads

Question 7

The resultant axial load on a bolt depends on

Accepted Answer

All of the above

Answer

Initial tension

Answer

External load applied

Answer

Relative elastic yielding (springness) of the bolt and the connected member

Question 8

Which of the following formula is used in designing a connecting rod?

Accepted Answer

Rankine's formula

Answer

Euler's formula

Answer

Johnson's straight line formula

Answer

Johnson's parabolic formula

Question 9

Which of the following statement is wrong for a connecting rod?

Accepted Answer

The most suitable section for the connecting rod is T-section

Answer

The connecting rod will be equally strong in buckling about X-axis and Y-axis, if $${l_{{	ext{xx}}}} = 4{l_{{	ext{yy}}}}$$

Answer

If $${l_{{	ext{xx}}}} > 4{l_{{	ext{yy}}}},$$ the buckling will occur about Y-axis

Answer

If $${l_{{	ext{xx}}}} < 4{l_{{	ext{yy}}}},$$ the buckling will occur about X-axis