<span>Mass of the copper penny m = 2.6 g
Atomic mass of copper = 63.55, Atomic number = 29,
So the number of neutrons = Atomic mass - Atomic number = 63 - 29 = 34
a. Neutron mass = 34 x (2.6 / 63.55) = 1.4 grams
Copper atoms per mole = 6.040 x 10^23 atoms/mol
moles of copper = 2.6 / 63.06 = 0.04123 mol
Total atoms in the copper = 6.040 x 10^23 atoms/mol x 0.04123 mol = 0.25 x 10^23 atoms
Number of electrons in the copper = 29 per atom
Mass of the electron = 9.085 x 10^-28 g
b. Electron mass = 0.25 x 10^23 x 29 x 9.085 x 10^-28 = 65.86 x 10^-5 g</span>
Answer:
This means C.the car uses 20% of the energy store in the gasoline for motion.
Explanation:
I hope this helps.
<span>The sparse area surrounding a spiral galaxy is called a
Halo
</span>
Answer:
During a total lunar eclipse, the moon and sun are on the exact opposite sides of the Earth, leaving the moon entirely in the Earth's shadow. During a partial lunar eclipse, only part of the moon is in the Earth's shadow.
Explanation:
Answer:
the resistance of the longer one is twice as big as the resistance of the shorter one.
Explanation:
Given that :
For the shorter cylindrical resistor
Length = L
Diameter = D
Resistance = R1
For the longer cylindrical resistor
Length = 8L
Diameter = 4D
Resistance = R2
So;
We all know that the resistance of a given material can be determined by using the formula :

where;
A = πr²

For the shorter cylindrical resistor ; we have:

since 2 r = D


For the longer cylindrical resistor ; we have:

since 2 r = D



Sp;we can equate the shorter cylindrical resistor to the longer cylindrical resistor as shown below :




Thus; the resistance of the longer one is twice as big as the resistance of the shorter one.