Question

A meterstick balances at its center. If an 86-g necklace is suspended from one end of the meterstick, the balance point moves 8.2cm toward that end.

a.) Is the mass of the meterstick grester than, less than, or equal to the mass of the necklace? Explain.

b.) Find the mass of the meterstick.

Answer 1

a)The mass of meterstick will be greater than the mass of neclace.

b)T A--------N---C------------B, Let AB be the metre stick.
C is its center.
AC = BC = 50 cms.

N is the balancing position with the necklace.
CN = 82cms.
C is the balancing position without necklace.
A is the position of the necklace.
C is the center of gravity through which the weight of the stick acts downwards.
A is the point through which the weight of the necklace acts downwards.
AN = 50 - 8.2=41.8 cms.
Let "m" be the weight of the necklace
Let 'N' be the fulcrum

By law of moments,
Sum of clockwise moments = Sum of anticlockwise moments
86 gm x 8.2 cm = 'm' x 41.8
"m" = 16.87 gm