A body of mass 36kg falls through a viscous liquid which offers a drag force of 260N on the body. The upthrust on the body at terminal velocity is?
[g = 10ms\(^2\)]
A
100N
B
620N
C
50N
D
310N
Verified Correct Answer: A.
Physical Principles & Numerical Solution
For anybody falling through a viscous liquid, at its terminal velocity. the resultant force acting on its is zero. from the equation: Mg - v - u = 0. where v = viscous drag
U = upthrust Mg = weight of the body.
∴ 36 x 10 - 260 - U = 0
∴ U = 360 - 260 = 100N
Upthrust on the body = 100N.
Source: Myschool Past Questions Archive (Record #13746)