Answer:
Red light
Explanation:
The energy emitted during an electron transition in an atom of hydrogen is given by

where
is the energy of the lowest level
n1 and n2 are the numbers corresponding to the two levels
Here we have
n1 = 3
n2 = 2
So the energy of the emitted photon is

Converting into Joules,

And now we can find the wavelength of the emitted photon by using the equation

where h is the Planck constant and c is the speed of light. Solving for
,

And this wavelength corresponds to red light.
Answer:
w = 4,786 rad / s
, f = 0.76176 Hz
Explanation:
For this problem let's use the concept of angular momentum
L = I w
The system is formed by the two discs, during the impact the system remains isolated, we have the forces are internal, this implies that the external torque is zero and the angular momentum is conserved
Initial Before sticking
L₀ = 0 + I₂ w₂
Final after coupling
= (I₁ + I₂) w
The moments of inertia of a disk with an axis of rotation in its center are
I = ½ M R²
How the moment is preserved
L₀ = 
I₂ w₂ = (I₁ + I₂) w
w = w₂ I₂ / (I₁ + I₂)
Let's reduce the units to the SI System
d₁ = 60 cm = 0.60 m
d₂ = 40 cm = 0.40 m
f₂ = 200 min-1 (1 min / 60 s) = 3.33 Hz
Angular velocity and frequency are related.
w₂ = 2 π f₂
w₂ = 2π 3.33
w₂ = 20.94 rad / s
Let's replace
w = w₂ (½ M₂ R₂²) / (½ M₁ R₁² + ½ M₂ R₂²)
w = w₂ M₂ R₂² / (M₁ R₁² + M₂ R₂²)
Let's calculate
w = 20.94 8 0.40² / (12 0.60² + 8 0.40²)
w = 20.94 1.28 / 5.6
w = 4,786 rad / s
Angular velocity and frequency are related.
w = 2π f
f = w / 2π
f = 4.786 / 2π
f = 0.76176 Hz
Answer:
500000N/m²
5250N
Explanation:
Given parameters:
Depth(H) = 50m
Density of water = 1000kg/m³
Acceleration of free fall = 10m/s
Unknown:
Pressure the water exerts on the diver = ?
Solution:
Pressure is the force per unit area on a body. In fluids, pressure is the product of density, gravity and height
Pressure in fluids = Density x acceleration due to gravity x height
Input the variables and solve;
Pressure in fluids = 1000 x 10 x 50 = 500000N/m²
B.
width of window = 150mm
height of window = 70mm
Force water exerts on the window = ?
To solve this problem;
Pressure = 
Area of the window = width x height = 150 x 10⁻³ x 70 x 10⁻³
= 1.05 x 10 ⁻²m²
Force = pressure x area
Input the variables;
= 500000N/m² x 1.05 x 10 ⁻²m²
= 5250N