The displacement of a flat faced follower when it has contact with the flank of a circular arc cam, is given by (where R = Radius of flank, r<sub>1</sub> = Minimum radius of the cam and θ = Angle turned through by the cam)

The displacement of the reciprocating roller follower, when it has contact with the straight flanks of the tangent cam, is given by (where r₁ = Minimum radius of the cam, r₂ = Radius of the roller follower and $$\theta $$ = Angle turned by the cam from the beginning of the follower displacement)

A

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

B

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

C

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

D

$$\left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)\left( {\frac{{1 - \cos \theta }}{{\cos \theta }}} \right)$$

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

A

R(1-cosθ)

B

R(1-sinθ)

C

(R-r1)(1-cosθ)

D

(R-r1)(1-sinθ)

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

A

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

B

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

C

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

D

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

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

A

ω2×OQ

B

ω2×OQsinθ

C

ω2×OQcosθ

D

ω2×OQtanθ

Flat faced follower’s acceleration when in contact with a circular arc cam is given by _________

A

ω2(R-r1)

B

ω2(R+r1)sin φ

C

ω2(R-r1)cos φ

D

ω2(R+r1)cos φ

From the given data, calculate the acceleration of follower in m/s2 at the beginning of the lift for a symmetrical tangent cam operating a roller follower. Least radius of the cam is 30 mm; Roller radius is 17.5 mm. The angle of ascent is 75° and the total lift is 17.5 mm. The speed of the cam shaft is 600 r.p.m.

A

187.6

B

185.5

C

183.2

D

190.1

A cam should be designed only using uniform rise and fall within half of the cam, the remaining is dwell period, and without any dwell period in between the rise -fall periods and rise and fall periods should be same. The maximum rise in follower is 30 mm. How much the follower will rise when the follower is 120 degrees from its initial position of a cam?

A

30

B

20

C

15

D

10

A cam should be designed only using uniform rise and fall within half of the cam, the remaining is dwell period, and without any dwell period in between the rise-fall periods and rise and fall periods should be same. The maximum rise in follower is 45 mm. How much the follower will rise when the follower is 45 degrees from its initial position of a cam?

A

22.5

B

0

C

30

D

15