Answer:
E = 15.7 KJ/mol
Explanation:
The number of vacancies in a metal is given by
n = n₀
They tell us that
n = 5 no
We replace
5 n₀ = n₀ e^{-E/KT}
-E / KT = ln 5
E = KT ln 5
E = 1,381 10⁻²³ 1170 ln 5
E = 2.6 10⁻²⁰ J
To take (J / mol) we multiply between Avogadro's number
E = 2.6 10⁻²⁰ 6.022 10²³
E = 1.57 10⁴ J / mol
E = 15.7 KJ/mol
Answer:
I'm not sure but, this video's pretty cool: gestyy.com/eyRkH2
Explanation:
pretty scary gameplay
Answer:
66.7 mph
Explanation:
Average speed = total distance / total time
We know the total distance is 200 miles. We need to find the total time.
During the first trip:
t = 100 mi / 100 mph
t = 1 h
During the second trip:
t = 100 mi / 50 mph
t = 2 h
So the average speed is:
s = 200 mi / 3 h
s = 66.7 mph
Round as needed.
Answer:
...as the height of an object increases, gravitational potential energy also increases
Are you sure the question is asking for the weight of the box? Sounds very much like a coefficient of friction-y sort of question to me.
Nevertheless, the <em>weight</em> of the box (assuming we're on Earth) is equal to <em>w=mg</em> so either 5 x 9.81 or 5 x 10 depending on what your qualification takes g to be.
Taking it to be 9.81 I will work out the coefficient of friction as well just incase that's what the question is really asking for:
20 = u x 49.05
u=20/49.05
u=0.41 to 2sf