Answer
(a) less than
(b) $0.080Kg$
Work Step by Step
(a) We know that the mass of the necklace is less than the mass of the meter stick as the moment arm of the necklace is greater than that of the meter stick.
(b) We can find the required mass as follows:
$\Sigma \tau=d(Mg)-r(mg)=0$
This simplifies to:
$m=\frac{dM}{r}$
We plug in the known values to obtain:
$m=\frac{(9.5)(0.34)}{50.0-9.5}$
$m=0.080Kg$
