Concept explainers
Conceptual Example 20.1 shows that the gravitational force between an electron and a proton is about 10−40 times weaker than the electric force between them. Since matter consists largely of electrons and protons, why is the gravitational force important at all?
To explain: The importance of gravitational force.
Answer to Problem 1FTD
Gravitational force is important because it acts on all the bodies and it binds everything in the whole universe together.
Explanation of Solution
Gravitational force is the weakest of all known forces in nature. The gravitational force is responsible for holding all the bodies. The gravitational force follows the inverse square law, just like the electrostatic force, but the difference in magnitude is very significant. The gravitational force between a proton and electron is
The strength of gravity decreases with distance but if the body is massive, it will have a higher magnitude of gravitational force. Gravity is important as it gives the body its weight. It is extends throughout the whole space and all bodies regardless of its size experience the gravitational force.
Conclusion:
Therefore, gravitational force is important because it acts on all the bodies and it binds everything in the whole universe together.
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