Answer:
The fraction of kinetic energy lost in the collision in term of the initial energy is 0.49.
Explanation:
As the final and initial velocities are known it is possible then the kinetic energy is possible to calculate for each instant.
By definition, the kinetic energy is:
k = 0.5*mV^2
Expressing the initial and final kinetic energy for cars A and B:


Since the masses are equals:

For the known velocities, the kinetics energies result:




The lost energy in the collision is the difference between the initial and final kinectic energies:


Finally the relation between the lost and the initial kinetic energy:


Answer:
117.6°
Explanation:
The vertical component of a force directed at some angle α from the vertical is ...
F·cos(α)
We want the vertical components of the wolf's force (Fw) and Red's force (Fr) to total zero. So for some angle from vertical α, Red's force will satisfy ...
Fw·cos(25°) + Fr·cos(α) = 0
cos(α) = -Fw/Fr·cos(25°) ≈ -(6.4 N)/(12.5 N)·0.906308 ≈ -0.464030
α ≈ arccos(-0.464030) ≈ 117.6°
Red was pulling at an angle of about 117.6° from the vertical.
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<em>Additional comment</em>
That's about 27.6° below the horizontal.
When light travels from a medium with higher refractive index to a medium with lower refractive index, there is a critical angle after which all the light is reflected (so, there is no refraction).
The value of this critical angle can be derived by Snell's law, and it is equal to

where n2 is the refractive index of the second medium and n1 is the refractive index of the first medium.
In our problem, n1=1.47 and n2=1.33, so the critical angle is
Weather is caused by different levels of humidity and the difference in the temperature of air which causes wind patterns. Energy from the sun evaporates the water on land. Air also heats up which brings up the water vapor to the atmosphere. This increases the humidity and the chance of rain. When hot is found near the land, this will create a high pressure which will prevent the formation of clouds and produce a fair weather.