a physics book is on top of a drafting table at 35 degree angle. Find the net external force acting on the book and determing wether the book move or remain at rest on this position. they give you:

force of friction 11N, force normal 18N,force of gravity on the book 22N.

The book will remain at rest if:

F -Fg -Ff = 0 = Fn,
F - 22 - 11 = 0,
F = 22 + 11 = 33N

To find the net external force acting on the book, we need to consider the forces acting on it. The forces at play here are the force of friction, the force normal, and the force of gravity.

1. Force of Friction: The force of friction opposes the motion of the book and acts horizontally. In this case, it has a magnitude of 11N.

2. Force Normal: The force normal is the perpendicular force exerted by the surface (drafting table) on the book. In this case, it has a magnitude of 18N.

3. Force of Gravity: The force of gravity always acts vertically downward towards the center of the Earth. In this case, it has a magnitude of 22N.

To determine whether the book moves or remains at rest, we need to compare the forces along both the horizontal and vertical axes.

Vertical Axis:
The force of gravity (22N) acting downwards is balanced by the force normal (18N) acting upwards. These two forces cancel each other out, resulting in zero net force in the vertical direction. Therefore, the book remains at rest or does not move vertically.

Horizontal Axis:
The book is inclined at a 35-degree angle, meaning there is a component of gravity and normal force acting along the horizontal axis. To determine the horizontal forces, we need to calculate the components of the force normal and the force of gravity.

- The horizontal component of the force normal is given by: force normal * cos(angle)
= 18N * cos(35°) = 14.83N

- The horizontal component of the force of gravity is given by: force of gravity * sin(angle)
= 22N * sin(35°) = 12.61N

So, the net external force acting on the book horizontally is the difference between the horizontal component of the force of gravity and the force of friction.

- Net External Force = (horizontal component of force of gravity) - (force of friction)
= 12.61N - 11N = 1.61N (approximately)

The net external force acting on the book is 1.61N. Since this force is non-zero, the book will move in the direction of the net force, which is along the horizontal axis.