Problem $1$: The following data supply to the clamp shown in the figure:

Acme thread

Single threading with $N=14$ thread$/$in

Outside diameter of $\frac{1}{2}$ in $=0\mathrm{.}5$ in $=do$

Root diameter of $0\mathrm{.}4350$ in $=dr$

$f$ and $f_c=0\mathrm{.}15$ and $0\mathrm{.}25,$ respectively

Collar radius of $0\mathrm{.}2in=>d_c=c\mathrm{.}4$ in

Operator can comfortably exert a force of $30$ lb at the end of the handle $F=30lb$

What is the clamping force developed between the jaws of the clamp?

What is the efficiency of the clamp?

Determine the maximum shear stress at the root of the thread