Answer:
1.33
Explanation:
Using the formula for destructive interference since the two reflected ray light waves from eyeglass should be made to cancel each other ( destructive interference) and also refractive index of air less than the refractive index of the film and both are less than the refractive index of the glass meaning the both reflected rays from the air and film will experience a phase change
n film = ( m + 0.5) ( λ / 2t)
since 2 t = ( m + 0.5) ( λ / n film)
where m is an integer, λ is wavelength, and t is thickness and n film is the refractive index of film
for effectiveness m = 0
n film = ( 0.5) ( 480 ÷ (2 × 90 ) ) = 1.33
According to KE = (3/2)kT
reducing temperature, in KELVIN, by half, average KE is reduced by half.
Answer:
Force of kinetic friction, Fk = 6N
Explanation:
Given the following data;
Coefficient of kinetic friction, μ = 0.2
Normal force, Fn=30N
To find the Force of kinetic friction;
Mathematically, the force of kinetic friction is given by the formula;
Fk = μFn
Where;
- Fk represents the force of kinetic friction.
- μ represents the coefficient of friction.
- Fn represents the normal force.
Substituting into the equation, we have;
Fk = 0.2*30
Fk = 6N
Therefore, the force of kinetic friction is 6N.
Answer:
.487 s⁻¹
Explanation:
Let damping constant be τ . The equation of decreasing amplitude can be written as
A = A₀ 
A / A₀ =
At t = 9.43 s , A / A₀ = .01
.01 = 
ln.01 = - 9.43 τ
-4.6 = -9.43τ
τ = .487 s⁻¹
