Two resistor of 2Ω in series parallel to resistor 5Ω in series to a 2Ω resistor. This configuration gives to us an equivalent resistor of 2.55Ω.
To solve this problem we have to use the rules of conection of resistor in series and parallel.
A resistor R1 in serie with other resistor R2 gives us an equivalent resistor Req= R1 + R2.
A resistor R1 in parallel with other resistor R2 gives us an equivalent resistor Req = R1.R2/R1+R2.
The circuit that show an arregement of resistor which we obtain a equivalent resistor of 2.5Ω from three resistor of 2Ω and 5Ω respectively is attached in the image:
The Sun is a main-sequence star, and, as such, generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 620 million metric tons of hydrogen and makes 616 million metric tons of helium each second.
If the billiard ball is going at the constant speed and contains its mass then the momentum WONT be changing. But realistically you have external forces like friction and air resistance changing the velocity thus changing the momentum. In this case momentum is not conserved because you're introduction an external force.
