Answer:
The thickness of the oil slick is 
Explanation:
Given that,
Index of refraction = 1.28
Wave length = 500 nm
Order m = 1
We need to calculate the thickness of oil slick
Using formula of thickness

Where, n = Index of refraction
t = thickness
= wavelength
Put the value into the formula



Hence, The thickness of the oil slick is 
Longitudinal waves travel through a series of compressions and rarefactions.
Answer:
(F)reaction = - 75 N
where, negative sign shows opposite direction.
Explanation:
This question can be answered using Newton's third law of motion. The Newton's Third Law of Motion states that for every action force there is an equal but opposite reaction force.
(F)action = - (F)reaction
Hence, in our scenario if we consider the 75 Newton force applied on the wall to be the action force then the reaction force of the wall must be equal to it in opposite direction. Therefore, the reaction push of the wall must be equal to 75 N.
<u>(F)reaction = - 75 N</u>
<u>where, negative sign shows opposite direction.</u>
Answer:
(a) 

(b) Kinetic Energy of planet with mass m₁, is KE₁ = 1.068×10³² J
Kinetic Energy of planet with mass m₂, KE₂ = 2.6696×10³¹ J
Explanation:
Here we have when their distance is d apart

Energy is given by

Conservation of linear momentum gives
m₁·v₁ = m₂·v₂
From which
v₂ = m₁·v₁/m₂
At equilibrium, we have;
which gives
multiplying both sides by m₂/m₁, we have

Such that v₁ = 

Similarly, with v₁ = m₂·v₂/m₁, we have

From which we have;
and

The relative velocity = v₁ + v₂ =
v₁ + v₂ = 
(b) The kinetic energy KE = 

Just before they collide, d = r₁ + r₂ = 3×10⁶+5×10⁶ = 8×10⁶ m
= 10333.696 m/s
=2583.424 m/s
KE₁ = 0.5×2.0×10²⁴× 10333.696² = 1.068×10³² J
KE₂ = 0.5×8.0×10²⁴× 2583.424² = 2.6696×10³¹ J.