That is the Sigma Symbol. It’s the addition of a sequence of numbers; the result is the sum of the total. if numbers are added sequentially from left to right, any intermediate result is a partial sum, prefix sum, or running total of the summation
Answer:
2.2 meters
Explanation:
Potential energy, PE created by a charge, q at a radius r from the charge source, Q, is expressed as:

is Coulomb's constant.
#The electric field,
at radius r is expressed as:

From i and ii, we have:


#Substitute actual values in our equation:

Hence, the distance between the charge and the source of the electric field is 2.2 meters
Answer:
A. Mass(only)
Explanation:
The correct answer is A because if the balloon is filled with air, it's filled with matter. Matter is anything that has space and occupies mass. The air occupies mass in the balloon but that doesn't mean that the balloon is heavier. People confuse themselves with mass and weight saying it means the same thing. Mass, like I said is the amount of matter an object contains whereas weight is how much an object weighs.
Answer:
Hydraulic press is called an instrument for multiplication of force. Why? Because it uses Pascal's idea and principle: F=p*S. If we apply small force to small piston you will generate a pressure. According to Pascal's law pressure is the same everywhere in closed system so the same pressure will act on large piston on the other side too.
Explanation: