Answer:
E = 19.89×10⁻¹⁶ J
λ = 1×10⁻¹ nm
Explanation:
Given data:
Frequency of xray = 3×10¹⁸ Hz
Wavelength of xray = ?
Energy of xray = ?
Solution:
speed of wave = wavelength × frequency
speed = 3×10⁸ m/s
3×10⁸ m/s = λ ×3×10¹⁸ s⁻¹
λ = 3×10⁸ m/s / 3×10¹⁸ s⁻¹
λ = 1×10⁻¹⁰m
m to nm:
λ = 1×10⁻¹⁰m×10⁹
λ = 1×10⁻¹ nm
Energy of x-ray:
E = h.f
h = plancks constant = 6.63×10⁻³⁴ Js
by putting values,
E = 6.63×10⁻³⁴ Js ×3×10¹⁸ s⁻
¹
E = 19.89×10⁻¹⁶ J
Because so objects are denser than water and some are less dense than water
B the girls arm will act as a pulley
Answer:
Option b. 9.59
Explanation:
First, let us calculate the pH. This is illustrated below:
[H3O+] = 3.9 x 10-5 M
pH = —Log [H3O+]
pH = —Log [3.9 x 10-5]
pH = 4.41
Recall: pH + pOH = 14
4.41 + pOH = 14
Collect like terms
pOH = 14 — 4.41
pOH = 9.59
