Question
Question: A plastic sphere is held below the surface of a lake by tying a thread at the bottom of the lake. Th...
A plastic sphere is held below the surface of a lake by tying a thread at the bottom of the lake. The tension in the thread is 900 N. The sphere has volume 0.65 m3. Find the mass of the sphere.
A
(a) 250 kg
A
(b) 340 kg
A
(c) 470 kg
A
(d) 560 kg
Explanation
Solution
(d)
T = V(σ - ρ)g = B – mg or mg = B – T
mg = 0.65 × 103 × 10 – 900 = 5600N or M = 560 kg