Chapter 4, Problem 4.5P

Interpretation Introduction

Interpretation: The magnitude and direction of the force that must be applied to the elbow to keep it in stationary position.

Concept introduction:

The magnitude of the force acting on the elbow to keep it in stationary is calculated by applying the force balance in $\text{x}\text{and}\text{y}$ direction.

The formula for calculate the total force in $\text{x}$ direction is,

  $F_x=\rho A{V}^2\left(1-\cos \beta \right)+F_{p,x}$

The resultant force is calculated by the following formula:

  $F=\sqrt{F_x^2+F_y^2}$

The formula for calculating the direction is,

  $\theta ={\tan }^{-1}\frac{F_y}{F_x}$