A turnbuckle is needed to apply an 8kN force on a cable. If the efficiency of the turnbuckle is 40% and the force applied is 159.155N with a lever of 20cm in length.
a)Find Mechanical Advantage:
M.A.=Load/Effort
M.A.=8000/159.155
M.A.=50.265 (ans.)
b)Find the velocity ratio:
Efficiency=M.A./V.R.
V.R.=M.A./eff.
V.R.=50.265/0.4
V.R.=125.66 (ans.)
c)Find the mean pitch of thread:
V.R.=distance moved by effort/dist. moved by load
V.R.=2piL/2*pitch of thread
2*pitch of thread=2pi*200mm/125.66
Pitch of thread=10/2
Pitch of thread=5mm (ans.)
Is this correct?
Yes, your calculations are correct.
For part a), you correctly calculated the mechanical advantage by dividing the load (8000 N) by the effort (159.155 N), giving a result of 50.265.
For part b), you correctly used the formula for efficiency (Efficiency = MA/VR) to find the velocity ratio. By dividing the mechanical advantage (50.265) by the efficiency (0.4), you obtained a velocity ratio of 125.66.
For part c), you correctly used the formula for velocity ratio (VR = distance moved by effort / distance moved by load). By rearranging the formula, you can solve for the pitch of the thread. You correctly substituted the values into the formula, using the lever length (20 cm or 200 mm) and the velocity ratio (125.66). After calculating, you correctly found that the mean pitch of the thread is 5 mm.
Great job! Your calculations are correct.