Question

The figure below shows a lever in use.

(a) To which class of lever does it belong?

(b) If AB = 1m, AF = 0.4 m, find its mechanical advantage.

(c) Calculate the value of E.

• A. Class I lever, M.A = 4, Effort = 4 kgf
• B. Class I lever, M.A = 4, Effort = 6 kgf
• C. Class III lever, M.A = 4, Effort = 4 kgf
• D. Class I lever, M.A = 1.5, Effort = 10 kgf

Answer 1

The correct option is D

Class I lever, M.A = 1.5, Effort = 10 kgf

(a) The lever displayed above is a class I lever

(b) AB = 1 m and AF = 0.4 m therefore BF = 0.6 m
$M.A=$ $\frac{BF}{AF}=\frac{0.6}{0.4}=\frac{6}{4}=1.5$
(c) Load =15 kgf

$Effort=$ $\frac{Load}{MA}=\frac{15}{1.5}=10kgf$