G stands for Newton's universal gravitational constant, whereas
g stands for the acceleration due to gravity at a certain point.
G = 6.67300 × 10-11 N.m2.kg-2. 
g = 9.8 ms-2.  
g is a variable quantity. 
G is a scalar quantity

Relationship between capital G and small g

The relationship between the capital letter G (G) and the lowercase letter g (g) lies in their distinct usage and representation in different contexts. While both letters are part of the Latin alphabet, they have different roles and characteristics.

G: Capital G
- Capital G (G) is the uppercase version of the letter g.
- It is typically used at the beginning of sentences, proper nouns, and titles.
- In physics, G is also used to represent the universal gravitational constant, which is a fundamental constant that appears in Isaac Newton's law of universal gravitation.

g: Small g
- Small g (g) is the lowercase version of the letter G.
- It is used in various contexts, including mathematics, physics, and engineering.
- In mathematics, g is commonly used as a variable to represent a function or a specific value within an equation.
- In physics, g often represents the acceleration due to gravity on Earth, which is approximately 9.8 m/s².
- The lowercase g is also used in computer programming as a variable or symbol to represent different concepts and operations.

Difference in usage and representation
- While both G and g are representations of the same letter, their usage and representation differ based on their case (uppercase vs. lowercase).
- Capital G is primarily used to start sentences, proper nouns, and titles, while small g is used in various mathematical and scientific contexts.
- In physics, G represents the universal gravitational constant, whereas g represents the acceleration due to gravity on Earth.
- In mathematics and computer programming, small g is commonly used as a variable or symbol to represent different values or functions.

In conclusion
In summary, the relationship between capital G and small g lies in their representation of the same letter in different cases. While capital G is primarily used at the beginning of sentences and proper nouns, small g is commonly used in mathematics, physics, and computer programming to represent variables, functions, and specific values. Understanding the context and usage of these letters is essential for effective communication and comprehension in various fields.