Rotation

In a closed system where no external torque acts, the angular momentum remains constant (law of conservation of angular momentum). If external torques are present, the angular momentum of the system can change due to the torque causing rotation.

The energy that the object has when it's spinning is never "used up", unless

there's something acting on the object to rob energy from it. In our daily

experience on Earth, there's ALWAYS some friction acting on a spinning object.

The friction robs energy from it, and it eventually stops spinning. That's why

it's so hard for us to understand and accept Newton's law that tells us how

things REALLY work. An object in motion continues in motion unless it's acted

on by an external force. In other words, if something is moving, it doesn't take

any force or action to KEEP it moving. We just never see this happen on Earth,

because we can never set anything up WITHOUT any outside forces that act

to make it stop, so we always have to do something to keep it moving.

A centripetal force acts towards the center of the circle, continually changing the object's direction towards the center. This force prevents the object from moving in a straight line and keeps it moving in a circular path.

No, a body in translatory motion does not have angular momentum as angular momentum is associated with rotational motion. Translatory motion involves motion along a straight line, while angular momentum involves rotation around an axis.

The formula for centripetal acceleration is a = v^2 / r, where a is the centripetal acceleration, v is the velocity of the object, and r is the radius of the circular path. The force required to produce this acceleration is given by F = m * a, where F is the centripetal force, m is the mass of the object, and a is the centripetal acceleration.

Centrifugal force is not a real force, but rather an apparent outward force that arises in a rotating reference frame. It is a result of inertia and is experienced by objects moving in a circular path due to their inertia trying to move in a straight line, away from the center of rotation.

Angular acceleration is typically expressed in units of radians per second squared (rad/s^2).

Yes, the blade of a fan that is turned on does have angular momentum because it is rotating around an axis. The angular momentum depends on the rotational speed of the blade and its moment of inertia.

Force is used to create movement in the human body, such as when muscles contract to move a limb. Torque, on the other hand, refers to the rotational force created when a force is applied at a distance from a pivot point, such as when throwing a ball or lifting a weight. Both force and torque are essential for various movements and functions in the human body.

Angular acceleration is equal to zero when an object is rotating at a constant angular velocity without any change in its rotational speed. This occurs when the net torque acting on the object is zero, meaning that there are no external forces causing the object to accelerate or decelerate rotationally.

The spin is forced on to the bullet or shell by grooves in the gun barrel, this is to take advantage of the fact that the axis of a rotating object will tend to remain parallel, this , in effect keeps the shell or bullet in a good aerodynamic profile, without tumbling (which absorbs energy). These grooves are known as rifling and so any weapon which has those grooves in the barrel is said to be rifled.

The amount of centripetal force on a mass moving in a circle is calculated by multiplying the mass of the object by the square of its velocity, and then dividing the result by the radius of the circular path. This can be represented by the formula Fc = mv^2/r, where Fc is the centripetal force, m is the mass, v is the velocity, and r is the radius.

Inertia varies depending on an object's mass. The greater the mass of an object, the greater its inertia. The shape and size of an object can also affect its inertia.

A centripetal force does not do work on a circularly moving object because the force is always directed towards the center of the circle, while the object moves tangentially to the circle. Since work is defined as force acting in the direction of displacement, the centripetal force and the displacement are perpendicular to each other, resulting in no work being done.

To change the speed without changing the angular momentum, you can change the radius of the rotating object. This is because angular momentum is the product of an object's moment of inertia, its mass, and its angular velocity. By adjusting the radius while keeping the other factors constant, you can alter the speed without affecting the angular momentum.

Centripetal acceleration is directed towards the center of the circle because it is the force that keeps an object moving in a circular path. Given that an object moving in a circular path is constantly changing its direction, the centripetal acceleration is necessary to ensure that the object remains on the curved path rather than moving in a straight line.

The angular speed of a motor depends on its design and specifications. To calculate the angular speed, you would need to know additional information such as the motor type (e.g., induction motor, synchronous motor), number of poles, and operating frequency. Without this information, it is not possible to provide a specific angular speed for a 3000-watt motor.

Most, but not all, spiral galaxies rotate in the same direction - clockwise as seen from Earth.

Some, like the Black Eye Galaxy, have an inner region that rotates in the opposite direction to the outer region.

Angular velocity is inversely proportional to the radius of rotation. This means that as the radius increases, the angular velocity decreases, and vice versa. Mathematically, the relationship can be expressed as ω = v/r, where ω is the angular velocity, v is the linear velocity, and r is the radius.

Usually radians per second.

Any unit is appropriate, if it consists of (a unit of angle) divided by (a unit of time)

Angular momentum is a physical quantity that represents the rotational motion of an object around an axis. It is the product of an object's moment of inertia and its angular velocity. In simpler terms, it describes how fast an object is spinning around a fixed point.

Speed refers to how fast an object is rotating or moving, while torque is the force that causes an object to rotate around an axis. Speed is measured in units like revolutions per minute (RPM) or meters per second, while torque is measured in units like Newton-meters or foot-pounds. In a mechanical system, speed and torque are related through the equation power = torque x speed, where power represents the rate at which work is done.