Cobalt has an atomic number (Z) of 27, which means the nuclei of all its isotopes have 27 protons. Cobalt 60 has an atomic mass of 60, so it has 60-27 = 33 neutrons.
The mass of 27 isolated protons plus the mass of 33 isolated neutrons would be:
27*(1.007825 u) + 33*(1.008665 u) = 60.497220 u
The actual mass of the nucleus of 60-Co is 59.933820 u.
Mass defect: 60.497220 u - 59.933820 u = 0.563400 u
The mass defect is equal to the binding energy of a nucleus.
using the fact that 1 u = 931.5 MeV/c^2
(0.563400 u)*(931.5 MeV/u) = 524.807 MeV
There are 105 in 6th grade because there are 75 boys right? So it said the ratio of girls is 7 and the ratio of boys is 5 so I divided 75 to 5 = 15 and I multiply 7 to 15 and got 105 girls.
Each notch should equal -3 (the difference between -10 and -4 is 6), meaning that the blue dot should be -19
Answer:
28 inches
Step-by-step explanation:
The circumference is given by
C = pi *d
C = 22/7 ( 9)
C =198/7
=28.28571429 inches
