Mass defect is the difference of the mass of the constituent particles (protons and neutrons) of the actual mass of the nucleus. The mass of a nucleus is actually less than the mass of the protons and neutrons.
This is how you calculate it for this problem.
lithium - 7 => 3 protons and 4 neutrons
mass of 3 protons = 3 * 1.007276 amu = 3.021828 amu
mass of 4 neutrons = 4 * 1.008665 amu = 4.03466
=> mass of 3 protons + 4 neutrons = 3.021828 amu + 4.03466 amu = 7.056488
Mass defect = mass of 3 protons and 4 neutrons - atomic mass of lithium =
Mass defect = 7.056488 amu - 7.016003 amu = 0.040485 amu
In a closed primary, only voters registered with a given party can vote in that party's primary.
The momentum of a fast object compared to that of a slow object even if they both have the same mass, is their velocities.
Having same mass but different velocities results in different momentum.
Example: mass = 10kg
Velocity 1 = 50 Velocity 2 = 100
Momentum 1 = 10×50 = 500 Ns
Momentum 2 = 10×100 = 1000 Ns
Hope it helped!
