Answer:
- Increases levels of well-being neurotransmitters
- Improves fitness
- Improves mental health
- Reduces the risk of developing diseases
Explanation:
Performing physical activities helps to build a healthy relationship with yourself, in the sense that physical activity promotes health at all levels. Health is a set of physical, mental and social well-being, so physical activity reaches all these levels and increases the quality of life for a person as a whole.
There are several types of physical activities that can be performed and you can choose the one that best fits your preferences and routine. A walk for example can be done in any safe place and at any time and it already helps in improving physical conditioning, in receiving serotonin and endorphins, in reducing blood pressure and protecting the heart and in improving mental health.
So the ideal is for each person to set their own goals in relation to their health and seek to achieve them, either to have a better quality of life, to socialize more with people, to prevent diseases, etc.
2. A dilute solution means that the amount of solvent (water, for this particular case) is significantly larger than the solute (salt). Thus, the answer is D.
6. John Dalton's atomic theory states that matter is made up of tiny indestructible objects called matter. The theory also indicates that although same elements have the same atoms, each element have unique set atoms that deinfe them. From this, we can conclude that the wrong assumption is C.
9. Atoms, by default, are electrically neutral. When an atom loses or gains electron/s, then they become ionized atoms or commonly called as ions. Thus, ionized atoms imply unequal number of protons and electrons. This means the answer must be A.
11. Analgesics are commonly used to relieve pain. Thus, the answer is C.
14. Adding up the atomic mass of the individual atoms will give you the molar mass of a compound. Therefore, the answer is B.:
15. The pH scale provides us the alkalinity or acidity of a solution based on the value. A value between 0 to 6 indicates that the solution is acidic. 7 is considered neutral and a value between 7 and 14 indicates that the solution is basic. Thus, the answer is D.
19. An element has consistent properties and can no longer be further identified into having individual properties. Thus, the answer is A.
20. The valence of an element dependeds on the number of electrons on the outermost shell. Thus, it is equal to the number of charge negative or positive charges on the ion. Hence, we have A<span>.
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Answer:
All three pendulum will attain same velocity
Explanation:
All three pendulum will attain same velocity irrespective of their mass difference in isolated system (means where air drag are negligible) and at same length
As you know when velocity is calculated we can not take mass into account.
Answer:
Boyle's Law
![\therefore P_1.V_1=P_2.V_2](https://tex.z-dn.net/?f=%5Ctherefore%20P_1.V_1%3DP_2.V_2)
Explanation:
Given that:
<u><em>initially:</em></u>
pressure of gas, ![= P_1](https://tex.z-dn.net/?f=%3D%20P_1)
volume of gas, ![= V_1](https://tex.z-dn.net/?f=%3D%20V_1)
<em><u>finally:</u></em>
pressure of gas, ![= P_2](https://tex.z-dn.net/?f=%3D%20P_2)
volume of gas, ![= V_2](https://tex.z-dn.net/?f=%3D%20V_2)
<u>To solve for final volume</u>
<em>According to Avogadro’s law the volume of an ideal gas is directly proportional to the no. of moles of the gas under a constant temperature and pressure.</em>
<em>According to the Charles' law, at constant pressure the volume of a given mass of an ideal gas is directly proportional to its temperature.</em>
But here we have a change in the pressure of the Gas so we cannot apply Avogadro’s law and Charles' law.
Here nothing is said about the temperature, so we consider the Boyle's Law which states that <em>at constant temperature the volume of a given mass of an ideal gas is inversely proportional to its pressure.</em>
Mathematically:
![P_1\propto \frac{1}{V_1}](https://tex.z-dn.net/?f=P_1%5Cpropto%20%5Cfrac%7B1%7D%7BV_1%7D)
![\Rightarrow P_1.V_1=k\ \rm(constant)](https://tex.z-dn.net/?f=%5CRightarrow%20P_1.V_1%3Dk%5C%20%5Crm%28constant%29)
![\therefore P_1.V_1=P_2.V_2](https://tex.z-dn.net/?f=%5Ctherefore%20P_1.V_1%3DP_2.V_2)
To determine the centroid of the object first moment of area is used.
To predict the resistance of a shape to bending and deflection which are directly proportional, second moment of area is used.