Answer:
Correct answer: (a) Ekmax = 1.3 · 10⁻¹⁹ J, (b) ε = 5 eV, (c) f = 1.21 · 10¹⁵ Hz
Explanation:
Given:
photon energy ε = 8 · 10⁻¹⁹ J
work function for metal Wf = 6.7 · 10⁻¹⁹ J
(a) Ekmax = ?
The Einstein equation for photo effect is:
ε = Wf + Ekmax ⇒ Ekmax = ε - Wf
Ekmax = 8 · 10⁻¹⁹ - 6.7 · 10⁻¹⁹ = 1.3 · 10⁻¹⁹ J
Ekmax = 1.3 · 10⁻¹⁹ J
(b) ε = ? eV
the relationship between 1 eV and 1 J is:
1 eV = 1.6 · 10⁻¹⁹ J
so the energy of one photon in eV equals:
ε = 8 · 10⁻¹⁹ J = 8 · 10⁻¹⁹ / 1.6 · 10⁻¹⁹ eV = 5 eV
ε = 5 eV
(c) f = ?
the energy of a single photon is calculated according to the formula:
ε = h · f
where is:
h = 6.62 · 10⁻³⁴ J s plank constant
and f frequency of each photon (electromagnetic radiation)
f = ε / h = 8 · 10⁻¹⁹ J / 6.62 · 10⁻³⁴ J s = 1.21 · 10¹⁵ s⁻¹ = 1.21 · 10¹⁵ Hz
f = 1.21 · 10¹⁵ Hz
God is with you!!!
Answer:
Explanation:
Given that,
The elevator is moving up and slowing down at the rate of, 
The acceleration due to gravity, 
Mass of the person, m = 93.3 kg
To find,
The reading of the scale.
Solution,
As the elevator is moving down with some acceleration. The net force acting on it is given by :
So, the scale will read 1194.24 N.
The correct answer is option B
Load
Reason:
in any electrical circuits loads uses electricity. Some of the common examples of load are electrical appliances, lights etc
Answer:
Color, however, is the least useful property for mineral identification. One reason is that many minerals have similar colors. Also, impurities can turn colorless minerals into colored minerals.
Explanation:
