Final answer:
A push or pull on an object is called a force. Work is done when a force causes displacement of the object in the force's direction, which is not merely based on the effort used but the force applied over a distance. Contact and field forces are two types of forces, with work and power being related concepts.
Step-by-step explanation:
A push or pull on an object is called a force. In physics, when we apply a force over a distance, we do work. According to scientific principles, work occurs when there is a displacement of the object in the direction of the force. It is important to understand that the amount of work done is determined by the product of the force applied in the direction of the movement and the magnitude of the displacement, not by the effort exerted alone.
Forces are of different types and magnitudes. Contact forces occur due to direct physical contact between two objects, such as friction, while field forces like gravity act without direct contact. Work done by a force can be positive or negative, depending on the direction of force and displacement. For example, friction does negative work because it opposes the movement.
Moreover, energy can be transferred by work, and power is defined as the rate at which work is done or energy is transferred. Understanding the concepts of force, work, energy, and power is essential for grasping the principles of physics and mechanics.