Answer:
The shortest de Broglie wavelength for the electrons that are produced as photoelectrons is 0.81 nm
Explanation:
Given;
wavelength of ultraviolet light, λ = 270 nm
work function of the metal, φ = 2.3 eV = 2.3 x 1.602 x 10⁻¹⁹ J = 3.685 x 10⁻¹⁹ J
The energy of the ultraviolet light is given by;
The energy of the incident light is related to kinetic energy of the electron and work function of the metal by the following equation;
E = φ + K.E
K.E = E - φ
K.E = (7.362 x 10⁻¹⁹ J) - (3.685 x 10⁻¹⁹ J )
K.E = 3.677 x 10⁻¹⁹ J
K.E = ¹/₂mv²
mv² = 2K.E
velocity of the electron is given by;
the shortest de Broglie wavelength for the electrons is given by;
Therefore, the shortest de Broglie wavelength for the electrons that are produced as photoelectrons is 0.81 nm
Answer:
Because a person may be pulled in the direction of the moving train. Thereby causing accident
Explanation:
According to Daniel Bernoulli's theorem, he was widely known as a Mathematician. He stated that due to the higher velocity of a moving train, there is higher kinetic energy in terms of volume around it, while the air pressure between the person and the train becomes lower.
As a result, a person near a moving train may be pulled in the direction of the moving train. Thereby causing accidents that may lead to death.
Answer:
Explanation:
Intensity is given by the expresion:
where:
Io = inicial intensity
r1= initial distance
r= final distance
Answer:
The new separation distance between adjacent bright fringes will be <u>4 mm</u>
Explanation:
Since, the distance between adjacent bright fringes is given by the formula:
Δx₁ = λL/d = 2 mm -------- eqn (1)
where,
Δx = Distance between adjacent bright fringes
λ = wavelength of light = constant for both cases
L = Distance between the slits and the screen
d = slit separation
Now, for the second case:
Slit Separation = d/2
Therefore,
Δx₂ = λL/(d/2)
Δx₂ = 2(λL/d)
using eqn (1), we get:
Δx₂ = 2 Δx₁
Δx₂ = 2(2 mm)
<u>Δx₂ = 4 mm</u>
Answer:
V = 15m/s
Explanation:
Given the following data;
Initial velocity = 3m/s
Time = 8secs
Acceleration = 1.5m/s²
To find the final velocity, we would use the first equation of motion;
V = U + at
Substituting into the equation, we have
V = 3 + 1.5*8
V = 3 + 12
V = 15m/s
