Answer:
I answered Number 4 (Solids and Elasticity)
Explanation:
solids and elasticity
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:
The answer to your question is:
a) 2.7 m/s²
b) -3.6 m/s²
Explanation:
Data
mass of the toolbox = 3.2 kg
a = ?
F = 40 N and F = 20 N
g = 9.81 m/s²
Formula
Second law of motion = F = ma
a + g = F / m
a = F/m - g
a) a = 40/3.2 - 9.81
a = 2.69 ≈ 2.7 m/s² positive up
b) a = 20/ 3.2 - 9.81
a = 6.25 - 9.81
= - 3.56 ≈ - 3.6 m/s² negative down
Answer:
D. The net electrical charge of the Earth.
Explanation:
All the other three choices affect the gravitational force. I remember from middle school.