Light<span> refracts whenever it </span>travels<span> at an angle into a substance with a </span>different<span>refractive index (optical density). This change of direction is </span>caused<span> by a change in speed. For example, when </span>light travels<span> from air into water, it slows down, causing it to continue to travel at a </span>different<span> angle or direction.</span>
Answer:

Explanation:
Given that,
Initial speed, u = 0
Final speed, v = 40 m/s
Time, t = 2 s
We need to find the acceleration of the aircraft. We know that, acceleration is equal to the rate of change of velocity. So,

So, the acceleration of the aircraft is
.
Answer:
v₁ = 37.5 cm / s
Explanation:
For this exercise we can use that angular and linear velocity are related
v = w r
in the case of the spool the angular velocity for the whole system is constant,
They indicate the linear velocity v₀ = 25.0 cm / s for a radius of r₀ = 1.00 cm,
w = v₀ /r₀
for the outside of the spool r₁ = 1.5 cm
w = v₁ / r₁1
since the angular velocity is the same we set the two expressions equal
v1 =
let's calculate
v₁ =
v₁ = 37.5 cm / s
Vf^2 = Vi^2 + 2ad
a= 34 m/s^2
Vi = 0 m/s
d = 3400m
Vf = 480.83 m/s
a=v/t
t=v/a
t=480.83/34
t=14.142 s
Before positive psychology, the main focus was mostly pathology, that is, studying various psychological issues and sometimes finding ways to treat them, or sometimes not and just studying them for the sake of studying them and noting their occurrence.