Chapter 2, Problem 18A

Consider the suspension of Nellie in Figure 2.11. Name the three forces that act on her. What is your evidence that they cancel to zero?

To determine

The three forces acting on person N. Also, the evidence that all the three forces cancel to zero.

Answer to Problem 18A

The three forces acting on person N are:

Person N weight, right rope tension and left rope tension.

Since the body is at rest, so all the three forces will cancel to zero.

Explanation of Solution

Given:

The given figure is shown below.

  

Formula used:

The expression for the weight is,

  $W=mg$

Here, $m$ is the mass and $g$ is the acceleration due to gravity.

Calculation:

Consider the mass of person N as $m$ .

The three forces acting on person N are,

• The weight of person N that will act as a downward vertical force.
• The tension in right rope is acting along the rope.
• The tension in left rope is acting along the rope.

The weight of person N is,

  $W=mg$

At equilibrium condition, the net force on the system is equal to zero.The resultant of the rope tensions is same as the weight of person N, $T=mg$ .Hence, the net force on the system to be zero.