Answer:
e) none of the previous options
Explanation:
Draw a free body diagram of the ball. There are three forces:
- Weight force mg pulling down, where m is mass and g is gravity
- Buoyancy force ρVg pushing up, where ρ is the density of water, V is the displaced volume, and g is gravity
- Applied force F pushing down
The ball is not moving, so according to Newton's second law of motion, the sum of the forces is zero.
∑F = ma
ρVg − mg − F = 0
F = ρVg − mg
F = g (ρV − m)
Plugging in values:
F = (10 m/s²) ((1000 kg/m³) (0.01 m³) − 1.5 kg)
F = 85 N
