In a flat collar pivot bearing, the moment due to friction is proportional to

A $$\frac{{{\text{r}}_1^2 - {\text{r}}_2^2}}{{{{\text{r}}_1} - {{\text{r}}_2}}}$$
B $$\frac{{{\text{r}}_1^2 - {\text{r}}_2^2}}{{{{\text{r}}_1} + {{\text{r}}_2}}}$$
C $$\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}$$
D $$\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{{\text{r}}_1} - {{\text{r}}_2}}}$$

Correct Answer: $$\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}$$

Bissoy MCQ
#Mechanical Engineering #Theory of Machine

Related Questions

The frictional torque transmitted in a flat pivot bearing, considering uniform wear, is (where μ = Coefficient of friction, W = Load over the bearing and R = Radius of bearing surface)
A $$\frac{1}{2}$$μWR
B $$\frac{2}{3}$$μWR
C $$\frac{3}{4}$$μWR
D μWR
The frictional torque transmitted in a flat pivot bearing with assumption of uniform pressure is _________ as compared to uniform wear.
A Less
B More
C Same
D None of these
The frictional torque transmitted in a flat pivot bearing, considering uniform pressure is
A 1/2 × μ. W. R
B 2/3 × μ. W. R
C 3/4 × μ. W. R
D μ. W. R
The radius of a friction circle for a shaft rotating inside a bearing is (where r = Radius of shaft and $$\tan \varphi $$  = Coefficient of friction between the shaft and bearing)
A $${\text{r}}\sin \varphi $$
B $${\text{r}}\cos \varphi $$
C $${\text{r}}\tan \varphi $$
D $$\frac{{\text{r}}}{2}\cos \varphi $$
The frictional torque transmitted in a conical pivot bearing, considering uniform wear, is
A 1/2 × μ.W. R cosec α
B 2/3 × μ.W. R cosec α
C 3/4 × μ.W. R cosec α
D μ.W.R cosec α
The frictional torque transmitted in a conical pivot bearing with assumption of uniform pressure is __________ as compared to uniform wear.
A Less
B More
C Same
D None of these
The frictional torque transmitted in a truncated conical pivot bearing, considering uniform wear, is
A $$\frac{1}{2}\mu {\text{Wcosec}}\alpha \left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)$$
B $$\frac{2}{3}\mu {\text{Wcosec}}\alpha \left( {{{\text{r}}_1} + {{\text{r}}_2}} \right)$$
C $$\frac{1}{2}\mu {\text{Wcosec}}\alpha \left( {\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}} \right)$$
D $$\frac{2}{3}\mu {\text{Wcosec}}\alpha \left( {\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}} \right)$$
The frictional torque transmitted in a truncated conical pivot bearing, considering uniform pressure, is
A $$\frac{1}{2}\mu {\text{Wcosec}}\alpha \left( {{{\text{r}}_{\text{1}}} + {{\text{r}}_{\text{2}}}} \right)$$
B $$\frac{2}{3}\mu {\text{Wcosec}}\alpha \left( {{{\text{r}}_{\text{1}}} + {{\text{r}}_{\text{2}}}} \right)$$
C $$\frac{1}{2}\mu {\text{Wcosec}}\alpha \left( {\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}} \right)$$
D $$\frac{2}{3}\mu {\text{Wcosec}}\alpha \left( {\frac{{{\text{r}}_1^3 - {\text{r}}_2^3}}{{{\text{r}}_1^2 - {\text{r}}_2^2}}} \right)$$
The frictional torque transmitted in a conical pivot bearing, considering uniform pressure, is (where R = Radius of shaft and $$\alpha $$ = Semi-angle of the cone)
A $$\frac{1}{2}\mu {\text{WRcosec}}\alpha $$
B $$\frac{2}{3}\mu {\text{WRcosec}}\alpha $$
C $$\frac{3}{4}\mu {\text{WRcosec}}\alpha $$
D $$\mu {\text{WRcosec}}\alpha $$
When the bearing is subjected to large fluctuations of load and heavy impacts, the bearing characteristic number should be _________ the bearing modulus.
A 10 times
B 5 times
C 15 times
D 20 times

Next steps