The velocity of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by

The retardation of a flat faced follower when it has contact at the apex of the nose of a circular arc cam, is given by (where OQ = Distance between the centre of circular flank and centre of nose)

A

$${\omega ^2} \times {\text{OQ}}$$

B

$${\omega ^2} \times {\text{OQ}}\sin \theta $$

C

$${\omega ^2} \times {\text{OQ}}\cos \theta $$

D

$${\omega ^2} \times {\text{OQtan}}\theta $$

The acceleration of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by

A

$${\omega ^2}{\text{R}}\cos \theta $$

B

$${\omega ^2}\left( {{\text{R}} - {{\text{r}}_1}} \right)\cos \theta $$

C

$${\omega ^2}\left( {{\text{R}} - {{\text{r}}_1}} \right)\sin \theta $$

D

$${\omega ^2}{{\text{r}}_1}\sin \theta $$

The velocity of the reciprocating roller follower when it has contact with the straight flanks of the tangent cam, is given by (where $$\omega $$ = Angular velocity of the cam shaft)

A

$$\omega \left( {{{\text{r}}_1}{{\text{r}}_2}} \right)\sin \theta $$

B

$$\omega \left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)\sin \theta \sec 2\theta $$

C

$$\omega \left( {{{\text{r}}_1}{{\text{r}}_2}} \right)\cos \theta $$

D

$$\omega \left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)\cos \theta \,{\text{cosec2}}\theta $$

In a circular arc cam with roller follower, the acceleration in any position of the lift will depend only upon

A

Total lift, total angle of lift, minimum radius of cam and cam speed

B

Radius of circular arc, cam speed, location of centre of circular arc and roller diameter

C

Mass of cam follower linkage, spring stiffness and cam speed

D

Total lift, centre of gravity of the cam and cam speed

If a gas metal arc process uses a low arc voltage and the arc is continuously interrupted as the molten electrode metal fills up the arc gap is known as

A

ARC

B

Short ARC

C

ARC length

D

ARC blow

The period during which the cam follower remains at rest, when cam moves, is known as

A

Constant period

B

Fixed period

C

Dwell period

D

Idle period

The acceleration of the reciprocating roller follower when it has contact with the straight flanks of the tangent cam, is given by

A

$${\omega ^2}\left( {{{\text{r}}_1}{{\text{r}}_2}} \right)\left( {1 - {{\cos }^2}\theta } \right)$$

B

$${\omega ^2}\left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)\left( {1 + {{\cos }^2}\theta } \right)$$

C

$${\omega ^2}\left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)\left( {\frac{{2 - {{\cos }^2}\theta }}{{{{\cos }^3}\theta }}} \right)$$

D

$${\omega ^2}\left( {{{\text{r}}_1} - {{\text{r}}_2}} \right)\left( {1 - {{\sin }^2}\theta } \right)$$

Pharmacists recently conducted a study with respect to the reasons their customers purchased eye drops to soothe eye dryness. Dry eyes were more frequently experienced by customers who wore contact lenses than by custorners who did not wear contact lenses. The pharmacists concluded that wearing contact lenses, by itself, can cause contact wearers to have dry eyes.

A

An inherited condition can cause both weak eyesight and dry eyes

B

Physical exertion causes dry eyes in many people who wear contact lenses.

C

Most people who have dry eyes do not wear contact lenses.

D

Most people who wear contact lenses do not have dry eyes.

In a cam drive with uniform velocity follower, the sharp corners of the displacement diagram are rounded off at the beginning and at the end of each stroke. This is done

A

Because of difficulty in manufacturing cam profile

B

Because of loose contact of follower with cam surface

C

In order to have acceleration in beginning and retardation at the end of stroke within the finite limits

D

Because the uniform velocity motion is a partial parabolic motion

In DC arc welding, if leads are arranged in work as Negative pole of the welding arc and electrode as Positive pole of the welding arc, the arrangement is known as

A

Fusion

B

Reverse polarity

C

Forward welding

D

Direct polarity

The velocity of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by

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