Question

5: The length of fixed link of a crank and slotted lever
mechanism is 250 mm and that of the crank is 100
mm. Then what is ratio of cutting stroke to the time of
return stroke?
2657713145
1
1.5
0 1.71
1.75​

Answer 1

Answer:

wrll I think its 1.5! that's the closer answer on my answer. mark me pls

Answer 2

Given info : The length of fixed link of a crank and slotted lever mechanism is 250 mm and that of the crank is 100 mm.

To find : The ratio of cutting stroke to the time of return stroke.

solution : from diagram of crank and slotted lever mechanism,

cos(α/2) = length of fixed link of the crank/

length of fixed link of a crank and slotted lever mechanism

⇒cos(α/2) = 100mm/250mm = 2/5

⇒α/2 = cos¯¹(2/5) = 66.42°

⇒α = 132.84°

now the ratio of cutting stroke to the time of return stroke = (360° - α)/α

= (360° - 132.84°)/(132.84°)

= 1.71

Therefore the ratio of cutting stroke to the time of return stroke is 1.71