Frictional forces are exerting force against the basketball, causing it to stop.
<span>The correct answer is B. - It would take a ray of light 10.5 light years to travel from Earth to Epsilon Eridani, or vice-versa. Using our current technology it would take far longer than 21.0 years for a space ship from Earth to travel that far - I would have to guess many hundreds of years.</span>
The momentum of the
x-ray photon is p = h/lambda . Lambda is the wavelength (0.30nm=3x10^(-9)m) and
h is Planck's constant,(h=6.62607004 × 10-34<span> m2 kg / s).The
momentum is: 2.2 x 10^(-25).</span>
The momentum can be calculated
also as: p=mv, where m is the mass of the electron and v is the speed.
So v=p/m,p is known,and
also the mass of the electron (m=9.10938356 × 10-31<span> kilograms).</span>
v=2.2 x 10^(-25)/9.10938356
× 10-31<span> kilograms=0.24 x 10^6 m/s</span>
Because Na⁺ ion lacks an electron and O²⁻ has two extra electrons extra, to balance the charge, we need 2 Na⁺ ions.
All ions, atoms and molecules want to get to the minimum energy state, and that state is when the ion, atom, or molecule is neutral, that's why all of them want to balance their charges.
