In which situation is the gravitational force between two objects hard to detect? (options)
a. if the mass of each object is very small.
b. if the objects are very close together.
c. if the mass of one of the objects is very great.
d. if the mass of both objects is very great.

Hence, the correct option is (A) "If the mass of each object is very small".

Explanation:

The gravitational force between two objects is directly proportional to the product of masses and inversely proportional to the square of the distance between them.

The mathematical expression is given by :

d is the distance between masses

Gravitational force is one of the fundamental force in the universe. If the masses of objects is too small, then their interaction with each other is hard to detect.

Hence, the correct option is (A) "If the mass of each object is very small".

most voltage drop calculators want the distance between the source and destination. then internally, they double it so both the source and return wires are calculated. but you need to know which distance the calculator uses so you're not half of what you should be or double what you should be.

most circuit breakers will not take a #6 directly, so the electrician will have to splice on a smaller pigtail. you also have to upsize the grounding wire when you upsized the ungrounded (hot) wire (see note in 250.122). this will preclude using most cable assemblies, as a cable with #6 copper will most likely only have a #10 grounding conductor. you need a #6 grounding conductor if the circuit is 20a. a #8 cable is no better, as it will have a #10 grounding conductor too. but most 20a breakers will take a #8 directly.

in your related post, you didn't say what type of load this is. if it is a light or heater, voltage drop won't be a big issue. if this is a motor, the current needs are huge at startup and the voltage drop can pose a problem. if this is a motor, knowing if the motor is under much load during startup will answer the voltage drop effect (a saw is easier to start than a compressor).

the answer would be c. motion and direction

i hope this : )