<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>
The speed 
of the elevator at the beginning of the 8 m descent is nearly 4 m/s. Hence, option A is the correct answer.
We are given that-
the mass of the elevator (m) = 1000 kg ;
the distance the elevator decelerated to be y = 8m ;
the tension is T = 11000 N;
let us determine the acceleration 'a' by using Newton's second law of motion.
∑Fy = ma
W - T = ma
(1000kg x 9.8 m/s² ) - 11000N = 1000 kg x a
9800 - 11000 = 1000
a = - 1.2 m/s²
Using the equation of kinematics to determine the initial velocity.
² = ² + 2ay
= √ ( 2 x 1.2m/s² x 8 m )
= √19.2 m²/s²
= 4.38 m/s ≈ 4 m/s
Hence, the initial velocity of the elevator is 4m/s.
Read more about the Equation of kinematics:
brainly.com/question/12351668
#SPJ4
I think their distance is a measurement of : B. space in two dimension
In two-dimensional space, both directions located in the same plane , and the distance in locations only separated by width and length (there is no volume in this model)
Explanation:
Ans 1 ) As the gravity of a planet increases, there will be increase in thickness of atmosphere around that planet. The gravitational force of the planets holds the bulks of molecules of atmosphere (as gas will need higher escape velocity).
Ans 2) Mars is the easier planets among all other planets in our solar system as it lies in habitable zone and it as a moderate gravity (where live can survive). Well, there's lot of resources too.
Thanks for asking
Answer:
48 kmph
Explanation:
The question is asking you the kmph and that means the amount of kilometers travelled divided by the amount of hours. And if you want to think of it in a formula, SPEED = DISTANCE ÷ TIME
In this case, the amount of hours is 2.5 and the speed is 120km so 120/2.5 is 48
so the answer is 48 kmph
