Answer:
The mass of the counterweight is 0.6 kg
Step-by-step explanation:
From the artists sculpture and the description, we have;
The location of the center of mass, M, of the bird = 12 cm left horizontally from the pivot
The location, E, where the counter weight is to be added = 30 cm right horizontally from the pivot
The mass of the bird = 1.5 kg
Let x represent the mass of the counterweight
For equilibrium, taking the sum of moment about point A as 0, with the anticlockwise moment also taken as negative, we have;
Moment about a point = Mass × The acceleration due to gravity, g × Perpendicular distance from the point
x × g × 30 cm - 1.5 kg × g × 12 cm = 0
x × 30 cm = 1.5 kg × 12 cm
x = 1.5 kg × 12 cm /30 cm = 0.6 kg
x = 0.6 kg.
The mass of the counterweight = x = 0.6 kg