The net force acting on an object equals the applied force plus the force of friction. True or False
The correct answer and explanation is:
The statement is False.
The net force acting on an object is the total force that results from all the forces acting on the object. It is not just the sum of the applied force and the force of friction. Instead, the net force is calculated by combining all forces, including both the applied force and friction, but also any other forces such as normal force, gravitational force, tension, or any other external forces.
To clarify, the net force is the vector sum of all forces acting on an object, meaning the direction and magnitude of each force must be considered. The applied force refers to the force that is purposely exerted on an object (for example, pushing or pulling), and friction is the force that opposes motion between two surfaces. If these two forces are acting in opposite directions, the frictional force would subtract from the applied force.
Mathematically, the net force can be expressed as:
F_net = F_applied – F_friction
In some cases, additional forces need to be accounted for, such as:
- Gravity (F_gravity): The force that pulls the object downward.
- Normal force (F_normal): The force exerted by a surface to support the weight of an object resting on it.
For an object moving on a flat surface, the frictional force typically acts opposite to the direction of motion, so it would oppose the applied force. However, the net force is not simply the sum of these two forces; it depends on all the forces and their directions. For example, if the applied force exceeds the frictional force, the object will accelerate in the direction of the applied force. Conversely, if friction is greater than the applied force, the object will decelerate.