Answer:
200 nm is the thinnest film that produces a strong reflection for green light with a wavelength of 500 nm
Explanation:
If two reflected waves interfere constructively ,strong reflection is produced. Two reflected waves will experience a phase change
For constructive interference
for thinnest film m=1
refractive index should be taken for film n=1.25
thickness of the thinnest film is
Explanation:
Distance covered by the particle is given by:
Distance (d) = rate (v) × time (t)
Speed of Mary, v₁ = 50 mph
Speed of Jim, v₂ = 60 mph
It is assumed that, Mary and Jim leave at the same time. After one hour, Jim is 10 miles ahead.
Distance travelled by Jim, d₁ = (60t + 10)
Distance travelled by Mary, d₂ = 50t
The distance between Mary and Jim is greater than or equal to 100 miles.
So, Jim takes is 9 hours more than Mary to cover same distance. Hence, this is the required solution.
Answer:
a) a = 3.72 m / s², b) a = -18.75 m / s²
Explanation:
a) Let's use kinematics to find the acceleration before the collision
v = v₀ + at
as part of rest the v₀ = 0
a = v / t
Let's reduce the magnitudes to the SI system
v = 115 km / h (1000 m / 1km) (1h / 3600s)
v = 31.94 m / s
v₂ = 60 km / h = 16.66 m / s
l
et's calculate
a = 31.94 / 8.58
a = 3.72 m / s²
b) For the operational average during the collision let's use the relationship between momentum and momentum
I = Δp
F Δt = m v_f - m v₀
F =
F = m [16.66 - 31.94] / 0.815
F = m (-18.75)
Having the force let's use Newton's second law
F = m a
-18.75 m = m a
a = -18.75 m / s²