試題詳解

8. The falling velocity of the droplet may or may not be the same when using the force balance method or friction factor method. If not the same, there should be a reason behind that. Please choose the CORRECT answer.
(A) The falling velocities are the same, so there is no reason behind that.
(B) The falling velocities are not the same because the airflow is the creeping flow.
(C) The falling velocities are not the same because the air friction is dominant.
(D) The falling velocities are not the same because the density of the air can be ignored.
(E) The falling velocities are not the same because the viscosity of the air is not considered when using the friction factor method.