Question

: What will be the rpm of smaller
gear if a 180 mm dia meshes with 60 mm
dia gear and the bigger gear makes 60
rpm? ​

Answer 1

Given:

180 mm diameter meshes with 60 mm  diameter gear and the bigger gear makes 60  rpm.

To Find:

What will be the rpm of smaller  gear?

Solution:

$\mathbf{\textrm{Diameter of smaller gear}\ (D_{1})=60 \ mm}$

Speed of smaller gear  $\mathbf{=N_{1}}$

$\mathbf{\textrm{Diameter of larger gear}\ (D_{2})=180 \ mm}$

Speed of smaller gear  $\mathbf{=N_{2}= 60 \ RPM}$

Relation between diameter and speed of rotation of gear:

$\mathbf{\dfrac{N_{1}}{N_{2}}=\dfrac{D_{2}}{D_{1}}}$

On substituting respective value in above equation:

$\mathbf{\dfrac{N_{1}}{60}=\dfrac{180}{60}}$

$\mathbf{\dfrac{N_{1}}{60}=3}$

So:

$\mathbf{N_{1}=3\times 60}$

$\mathbf{N_{1}=180 \ RPM}$

Means speed of smaller gear is 180 RPM.

Answer 2

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Speed of smaller gear is 180 RPM.