C. Number of protons = atomic number; number of neutrons = mass number - atomic number
Answer:

direction is Horizontal
Explanation:
As we know that the string is horizontal here
so the tension force in the string is due to electrostatic force on it
now we will have

so here the force is tension force on it


now we have


direction is Horizontal
The best and most correct answer among the choices provided by your question is the second choice or letter C. A solar-powered car converts light energy to mechanical energy.
Solar cars use photovoltaic cells to convert sunlight into energy. Photovoltaic cells are the components in solar panels that convert the sun's energy to electricity<span>. They're made up of semiconductors, usually silicon, that absorb the light.
I hope my answer has come to your help. Thank you for posting your question here in Brainly.
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It runs slower <span>as gravity is lower so acceleration due to gravity is smaller</span>
Answer:
The force is 
Explanation:
From the question we are told that
The mass of the block is 
The coefficient of static friction is 
The coefficient of kinetic friction is 
The normal force acting on the block is

substituting values


Given that the force we are to find is the force required to get the block to start moving then the force acting against this force is the static frictional force which is mathematically evaluated as

substituting values


Now for this block to move the force require is equal to
i.e

=> 