Why is tension constant throughout a rope?

The tension in the rope is constant if its force does not have to be used to accelerate anything else, including itself. Therefore, if it has negligible mass and is held taut between two points, the tension will be considered constant throughout.

Does a frictionless pulley have tension?

that runs over a frictionless pulley, the upward tensions exerted by the rope on the two objects will be equal in magnitude. And if the rope is also inextensible, then the accelerations of the two objects will be equal in magnitude (although opposite in direction).

Why is tension different in pulley with mass?

Mass of the pulley plays insignificant role because they are generally of negligible mass compared to the mass lifted. But if it is of much larger mass than it will definitely affect the max tension in the string because than the force required to lif t a body will also have to overcome the inertia of the pulley also .

Is tension constant throughout a string?

A string or rope is often idealized as one dimension, having length but being massless with zero cross section. If there are no bends in the string, as occur with vibrations or pulleys, then tension is a constant along the string, equal to the magnitude of the forces applied by the ends of the string.

Does the mass of the rope affect tension?

Tension in the rope must equal the weight of the supported mass, as we can prove using Newton’s second law. If the 5.00-kg mass in the figure is stationary, then its acceleration is zero, and thus Fnet = 0. Thus, just as you would expect, the tension equals the weight of the supported mass: T = w = mg.

What is massless in tension?

A string having negligible mass compared to that of the object connected to it is called a massless string. Tension in a massless string is constant and always directed away from the body attached to it i.e. it is a pull force.

Why pulley is massless and frictionless?

The presence of friction and inertia in the pulley modifies the transmitted tension. Therefore, to make things simple, we often use the massless and frictionless pulley approximation. If the pulley has a mass “m”, then It has a moment of inertia I which is functiom of mass m.

What does it mean if a pulley is frictionless?

What we mean by a frictionless pulley is that the friction in the bearings of the pulley is negligible, and the pulley is free to rotate without any resistance. We don’t mean that the friction between the string and the pulley surface is negligible.

What happens when a pulley is not massless?

When the pulley is not massless, part of the driving force is diverted into accelerating the pulley’s rotation. The pulley can be considered a solid disc, with I = ½ mpR2, where R is the radius of the pulley. This results in a net clockwise torque and hence a clockwise angular acceleration in the pulley.

Why is tension constant in a massless rope?

In a massless rope, tension is constant unless a force is applied somewhere along the rope. Why? Because any differential tension would travel at infinite velocity (since speed of wave scales inversely with square root of mass per unit length, and the rope is massless).

Why is the tension in a pulley constant on both sides?

This is because, there is no resistive force offered from the surface of pulley to counter the tension. In case, the surface of the pulley is rough, it can offer more resistance to the rope, and hence force on both sides will be different.

Why pulleys are not massless?

In reality, pulleys are not massless. When a pulley is rotating, there has to be an unbalanced torque in the direction of rotation. This means the tension on both ends should be different, else force will be balanced. When an unbalanced torque acts the whole system accelerate and so does the rotation of the pulley.

Why does a pulley spin at an accelerating rate?

There needs to be a net torque on the pulley for it to spin at an accelerating rate, so the pull forward by the rope on the pulley must be greater than the pull back. There is a difference in tension. I don’t think the idea that a knot would make the tension not constant throughout a rope is correct (if the rope is ‘massless’).