its C because i just anwserd it & it was right
<span>E=hc/wav. len
E = (6.62 x 10^-34 x 3 x 10^8)/0.0275 x 10^-9
E = 7.22182 x 10^-15 J
To convert to eV divide by 1.6 x 10^-19
E = 7.22182 x 10^-15/1.6 x 10^-19 eV
E =45.36 x 10^3 eV
Th energy, E, of a single x-ray photon in eV is = 45.36keV.
Number of photons, n = total energy/ energy of photon
n = 3.85 x 10^-6/7.22182 x 10^-15
n = 5.33 x 10^8 photons </span>
Answer:
Explanation:
When two forces acting on a line of action and they are equal in magnitude but opposite it direction, it forms a couple.
Torque is defined as the product of either force and the perpendicular distance between the two forces.
It is a vector quantity.
The net torque is zero, it means the anticlockwise torque is equal to the clockwise torque.
It means they balances each other.
Answer:
6.575
Explanation:
T1 = 30C = 30 + 273 = 303 K
T2 = - 10 C = - 10 + 273 = 263 K
The coefficient of performance of heat pump
k = T2 / (T1 - T2)
k = 263 / (303 - 263) = 6.575
