Answer:
K.E = 5.53 eV = 8.85 x 10⁻¹⁹ J
Explanation:
First we calculate the energy of photon:
E = hc/λ
where,
E = Energy of Photon = ?
h = Plank's Constant = 6.626 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength = 120 nm = 1.2 x 10⁻⁷ m
Therefore,
E = (6.626 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(1.2 x 10⁻⁷ m)
E = (16.565 x 10⁻¹⁹ J)(1 eV/1.6 x 10⁻¹⁹ J)
E = 10.35 eV
Now, from Einstein's Photoelectric equation we know that:
Energy of Photon = Work Function + K.E of Electron
10.35 eV = 4.82 eV + K.E
K.E = 10.35 eV - 4.82 eV
<u>K.E = 5.53 eV = 8.85 x 10⁻¹⁹ J</u>
- The work done is -30 J
- The heat is 25 J
<h3>What is the heat and the work?</h3>
We know that the work done by a gas could be positive or negative same as the heat. If the work done is positive then work is done on the system.
The work done is obtained from;
W = PΔV
W = 1.0 x 105 Pa(0.0006 m³ - 0.0003 m³)
W = 30 J
Given that the gas absorbs heat from the surroundings and the gas is expanding.
- The work done is -30 J
- The heat is 25 J
Learn more about work done on a gas:brainly.com/question/12539457
#SPJ1
Answer:
4.6×10^-7 m or 0.46nm
Explanation:
From
Wo= hc/λ
Where:
Wo= work function of the metal
h= planks constant
c= speed of light
λ= wavelength
λ= hc/Wo
λ= 6.6×10^-34 × 3×10^8/4.30×10^-19
λ= 4.6×10^-7 m
I attached a Diagram for this problem.
We star considering the system is in equlibrium, so
Fm makes
with vertical
Fm makes 70 with vertical
Applying summatory in X we have,


We know that W is equal to

Substituting,




<em>For the second part we know that the reaction force Fj on deltoid Muscle is equal to Fm, We can assume also that</em> 