# Why is angular momentum conserved in an inelastic collision?

Angular momentum is conserved for this inelastic collision because the surface is frictionless and the unbalanced external force at the nail exerts no torque.

## How do you find angular momentum in AP physics?

To find the angular momentum of a point mass moving in a straight line, take the mass of the object times the velocity of that object, and either multiply by how far that object is from the axis times sine of the angle between the velocity vector and that R.

## What does angular momentum depend on?

Angular momentum depends on the rotational velocity of an object, but also its rotational inertia. When an object changes its shape (rotational inertia), its angular velocity will also change if there is no external torque.

## Is momentum a scalar or a vector?

momentum, product of the mass of a particle and its velocity. Momentum is a vector quantity; i.e., it has both magnitude and direction.

## What is r in angular momentum?

Angular Momentum Formula r is the radius (distance between the object and the fixed point about which it revolves)

## How do you calculate angular momentum?

With a bit of a simplification, angular momentum (L) is defined as the distance of the object from a rotation axis multiplied by the linear momentum: L = r*p or L = mvr.

## Why do we need angular momentum?

In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important quantity in physics because it is a conserved quantity—the total angular momentum of a closed system remains constant.

## What is the unit for angular momentum?

Appropriate MKS or SI units for angular momentum are kilogram metres squared per second (kg-m2/sec). For a given object or system isolated from external forces, the total angular momentum is a constant, a fact that is known as the law of conservation of angular momentum.

## How is angular momentum used in real life?

The classic example of this is a spinning ice skater or someone spinning in an office chair. By pulling in her arms, the skater decreases her moment of inertia (all her mass is closer to the middle), so her angular velocity has to increase in order to keep her angular momentum constant.

## Can you have angular momentum without linear momentum?

Angular momentum of a spinning object without linear momentum is proportional to rotational inertia and angular velocity.

## Under what conditions is momentum not conserved?

Momentum is not conserved if there is friction, gravity, or net force (net force just means the total amount of force). What it means is that if you act on an object, its momentum will change. This should be obvious, since you are adding to or taking away from the object’s velocity and therefore changing its momentum.

## Is torque a vector?

Torque is a vector quantity. The direction of the torque vector depends on the direction of the force on the axis.

## Is angular momentum a vector?

Angular momentum and torque are special vectors because they are the product of two other vectors – a position vector and a force or linear momentum vector.

## Is angular momentum constant?

Conservation of angular momentum is a physical property of a spinning system such that its spin remains constant unless it is acted upon by an external torque; put another way, the speed of rotation is constant as long as net torque is zero.

## Is momentum positive or negative?

Momentum is a vector and has the same direction as velocity v. Since mass is a scalar, when velocity is in a negative direction (i.e., opposite the direction of motion), the momentum will also be in a negative direction; and when velocity is in a positive direction, momentum will likewise be in a positive direction.

## Is momentum a force?

Momentum is the force that exists in a moving object. The momentum force of a moving object is calculated by multiplying its mass (weight) by its velocity (speed).

## Is velocity a vector?

Speed is a scalar quantity – it is the rate of change in the distance travelled by an object, while velocity is a vector quantity – it is the speed of an object in a particular direction.

## Is inertia a vector?

No, moment of inertia is a tensor quantity. Sometimes it behaves as scalar & sometimes as a vector. Sometimes it depends on the directions and sometimes depends on distribution of mass of the particles in the object.

## What is torque symbol called?

The symbol for torque is typically \boldsymbol \tau or τ, the lowercase Greek letter tau. When being referred to as moment of force, it is commonly denoted by M.

## Can angular velocity be infinite?

As such the corresponding angular velocity Uθ is literally zero everywhere and goes to infinity as we approach the singularity point.

## Why is angular momentum perpendicular?

Due to the mathematical properties of the vector product, if an object is moving in a 2D plane about a point that is also in that plane, then both r and v will lie in the plane, and the vectorproduct will be perpendicular to it.

## What is angular momentum example?

Angular Momentum is defined as the property of any rotating object given by the product of the moment of inertia and angular velocity of the rotating object. It is a vector and has both magnitude and direction. The common examples of angular momentum are the rotation and revolution of Earth. Its SI unit is Kgm2s-1.

## How is torque related to angular momentum?

Torque is the rotational equivalent of force and Angular Momentum is the rotational equivalent of Translational Momentum. This can be extended to rotational motion as follows, →τ=d→Ldt . So Torque is the rate of change of Angular Momentum.

## Do all objects have angular momentum?

When discussing the angular momentum of an object, the axis is taken to be one that goes through the center of mass. But each object has an angular momentum with respect to every axis. The earth has an angular momentum with respect to the polar axis, and another angular momentum with respect to the sun’s polar axis.