Answer:
The correct option is that (She decreases her moment of inertia, thereby increasing her angular speed.)
Explanation:
When an object is in circular motion, the vector that describes it is known as angular momentum. Angular momentum is conserved or constant when an object is spinning in a closed system and no external torques are applied to it. An example of conservation of angular momentum is seen when a woman is sitting on a spinning piano stool with her arms extended. Her angular momentum is conserved because the net torque on her is negligibly small as the friction is exerted very close to the pivot point.
When she folds her arms,her rate of spin increases greatly decreasing her moment of inertia. The work she does to pull in her arms results in an increase in rotational kinetic energy( that is, increase in her angular speed). I hope this helps, thanks!
Answer:
Base quantities are the minimum numbers of the physical quantities. Base quantities are defined as the physical quantities which can not be defined in terms of other physical quanities. There are seven base quantities. Physical Quantitie Units Derived Quantities are defined as those physical quantities which are derived from the base quantities.
Explanation:
A physical quantity is a property of a material or system that can be quantified by measurement. A physical quantity can be expressed as the combination of a numerical value and a unit. For example, the physical quantity mass can be quantified as n kg, where n is the numerical value and kg is the unit. A physical quantity possesses at least two characteristics in common, one is numerical magnitude and other is the unit in which it is measured.
Distinguish between a basic physical quantity and a derived physical quantity giving an example of each. Answers. Basic physical quantities are quantities which can be obtained without derivation. e.g Temperature. While derived physical quantities are quantities which can only be obtained from other physical quantities.
Omni-directional. It means all directional.
