At the entrance of most beaches, there is a bulletin board with notices about water conditions: maybe a faded sign warning about rip currents and a list of this week's tide tables. Most people pass them by without a second thought, but if you want to enter the ocean, it is important to know its movements, whether to avoid being caught in a riptide or to figure out when the waves will be at their best.
Hope this helps
Answer:
1.8 × 10⁻⁸ Hm
Explanation:
Given that:
The refractive index of the film = 19
The wavelength of the light = 136.8 μ m
The thickness can be calculated by using the formula shown below as:
Where, n is the refractive index of the film
is the wavelength
So, thickness is:
Thickness = 1.8 μ m
Since,
1 μ m = 10⁻⁸ Hm
So,
Thickness = 1.8 × 10⁻⁸ Hm
Answer:
Explanation:
This is case of interference in thin films
for constructive interference in thin film the condition is
2μ t = (2n+1)λ/2 ; μ is refractive index of oil , t is thickness of oil , λ is wave length of light .
2 x 1.28 x t = λ/2 , if n = 0
2 x 1.28 x t = 605 /2
t = 118.16 nm .
the minimum non-zero thickness of the oil film required = 118.16 nm.
Edit: You do mean Ridge?
Rocks near Mid-Ocean Ridge are younger than rocks near the trenches.
Seismic data shows oceanic crust is sinking into the mantle at the trenches.
Matching bands of magnetic rock are found on either side of the Ridge. Earth's magnetic fields change these bands over time.
'In transverse waves, the particles of the medium move perpendicular to the direction of the flow of energy' is true for transverse waves only.
'In longitudinal waves, the particles of the medium move parallel to the direction of the flow of energy' is true for longitudinal waves only.
'Many wave motions in nature are a combination of longitudinal and transverse motion' is true for both longitudinal and transverse waves.
<u>Explanation:</u>
Longitudinal waves are those where the direction of propagation of particles are parallel to the medium' particles. While transverse waves propagate perpendicular to the medium' particles.
As wave motions are assumed to be of standing waves which comprises of particles moving parallel as well as perpendicular to the medium, most of the wave motions are composed of longitudinal and transverse motion.
So the option stating the medium' particle moves perpendicular to the direction of the energy flow is true for transverse waves. Similarly, the option stating the medium' particle moves parallel to the direction of flow of energy is true for longitudinal waves only.
And the option stating that wave motions comprises of combination of longitudinal and transverse motion is true for both of them.
