Question

A force of $5kgf$ is required to cut a metal sheet. A shear is used for cutting a metal sheet; its load arm is $5cm$ long while its effort arm is $10cm$ long. What effort is needed to cut a sheet?

• A. 2.5 kgf
• B. 5.0 kgf
• C. 2.0 kgf
• D. 3.0 kgf

Answer 1

The correct option is A

2.5 kgf

Length of blades = Load arm = $5cm=5/100m$

Load $L=5kgf$

Effort needed, $E=?$

Effort arm = $10cm$ = $\frac{10}{100}m$

Effort $\times$ Effort arm = Load $\times$ Load arm

$\frac{E\times 10}{100}$= $\frac{5\times 5}{100}$

Effort = $\frac{25}{10}$ = $2.5kgf$