Answer:
C. her moment of inertia increases and her angular speed decreases
D. her moment of inertia increases and her angular speed decreases
Explanation:
The moment of inertia of a body is the sum of the products of an increment of mass and the square of its distance from the center of rotation. When a spinning person extends her arms, part of her mass increases its distance from the center of rotation, so increases the moment of inertia.
The kinetic energy of a spinning body is jointly proportional to the moment of inertia and the square of the angular speed. Hence an increase in moment of inertia will result in a decrease in angular speed unless there is a change in the rotational kinetic energy.
This effect is used by figure skaters to increase their spin rate by drawing their arms and legs closer to the axis of rotation. Similarly, they can slow the spin by extending arms and legs.
When the person extends her arms, her moment of inertia increases and her angular speed decreases.
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<em>Note to those looking for a letter answer</em>
Both choices C and D have identical (correct) wording the way the problem is presented here. You will need to check carefully the wording in any problem you may think is similar.
69 i agree with her hope this helps
Coordinator bond ! the three bond pair makes triple bond !
Answer:
evidence:
- fossils found in different parts of the world were the same
- weather patterns in different parts of the world
- mountain ranged with the same rock types, structures, and ages are now on opposite sides of the atlantic ocean
- coal was found in cold climates where it could not have formed
-scratches from glaciers were found in a desert
- continents fit like a puzzle
- identical rocks of the same type and age found on both sides of the atlantic ocean
<span>Calcium fluoride is produced. It is one Calcium atom bonded to two fluoride atoms. The Calcium atom receives one electron from one fluoride and a second electron from the second fluoride atom. As a result of receiving the two electrons, Calcium will have a negative charge. The two fluorides become positive from losing an electron. The positive and negative charge attraction keeps the atoms close together to form an ionic bond.</span>