The term "observer" refers to a frame of reference. In a ground fixed coordinate system the pendulum never moves backwards.Luca 123 said:I was told that the observer, standing still, would not observe any fictitious forces on the pendulum, so how does he explain the pendulum swinging backwards?
Fictitious forces, also known as inertial forces, are forces that appear to act on an object in a non-inertial frame of reference, but are actually a result of the object's acceleration in that frame. These forces do not arise from physical interactions and are therefore not considered true forces.
In an accelerating cart, an object inside the cart appears to experience a force pushing it in the opposite direction of the acceleration. This is known as the "inertial force" or fictitious force and arises due to the object's tendency to maintain its state of motion.
Newton's first law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. In an accelerating cart, the object appears to accelerate due to the cart's motion, even though no external force is acting on it. This is because the object has a natural tendency to resist changes in its motion, as explained by Newton's first law.
Fictitious forces have practical applications in the field of mechanics, as they can help in accurately predicting the motion of objects in non-inertial frames of reference. They are also used in engineering and design to account for the effects of acceleration on objects in moving systems.
No, fictitious forces cannot be eliminated in accelerating carts. They are an inherent consequence of using a non-inertial frame of reference and will always appear to act on objects in that frame. However, by understanding their origins and properties, we can account for them and accurately analyze the motion of objects in accelerating carts.