Which of the following represents the equation of motion of a steel ball thrown into a viscous liquid when it is moving with an acceleration a ?(A) W-V-U=ma (B)W-U=ma-V (C)W-U-V=0 (D)U-V=W

Respuesta :

Answer: A

Explanation: When a steel ball is thrown into a viscous liquid, three forces will act on the ball.

1.) The viscous drag force V which is acting upward

2.) The buoyant force U which is acting upward and

3.) The weight of the ball W. Which is acting downward.

When it is moving with an acceleration a, the weight W will be greater than U and V

Since Force = ma.

The resultant vector force will be

W - V - U = ma