D. they have a full luster
Answer:
s = 38.7 m
Explanation:
First we calculate the distance covered during uniform motion of reaction time.
s₁ = vt
where,
s₁ = distance covered during uniform motion = ?
v = uniform speed = 11 m/s
t = time = 2.3 s
Therefore,
s₁ = (11 m/s)(2.3 s)
s₁ = 25.3 m
Now, we calculate the distance covered during decelerated motion:
2as₂ = Vf² - Vi²
where,
a = deceleration = -4.5 m/s²
s₂ = distance covered during decelerated motion = ?
Vf = Final Velocity = 0 m/s
Vi = Initial Velocity = 11 m/s
Therefore,
2(-4.5 m/s²)s₂ = (0 m/s)² - (11 m/s)²
s₂ = (-121 m²/s²)/(-9 m/s²)
s₂ = 13.4 m
the total distance will be:
s = s₁ + s₂
s = 25.3 m + 13.4 m
<u>s = 38.7 m</u>
Consider the projectile launched at initial velocity V at angle θ relative to the horizontal.
Neglect wind or aerodynamic resistance.
The initial vertical velocity is Vsinθ.
When the projectile reaches its maximum height of h, its vertical velocity will be zero.
If the time taken to attain maximum height is t, then
0 = Vsinθ - gt
t = (Vsinθ)/g, where g = acceleration due to gravity.
The horizontal component of launch velocity is Vcosθ. This velocity remains constant because aerodynamic resistance is ignored.
The time to travel the horizontal distance D is twice the value of t.
Therefore
D = Vcosθ*[(2Vsinθ)/g]
= (2V²sinθ cosθ)/g
= (V²sin2θ)/g
In order for D (horizontal distance) to be maximum,

That is,

Because

, therefore cos(2θ) = 0.
This is true when 2θ = π/2 => θ = π/4.
It has been shown that the maximum horizontal traveled can be attained when the launch angle is π/4 radians, or 45°.
<span>A differences in the warmth, or moisture level as well as neighbouring areas of pressure in </span>air cause air<span> to circulate. in the earth's atmosphere.</span>
Answer:
D = 2.828 m
Explanation:
given,
distance of source of light = 1.24 m below surface of pool
refractive index of the water = n₁ = 1.33
refractive index of air = n₂ = 1
refraction angle be = 90°
let C be the critical angle
Radius = d tan C
d is the depth of the source
Using Snell's law
n₁ sin C = n₂ sin R
1.33 x sin C = 1 x sin 90°


C = 48.75°
hence,
R = 1.24 x tan 48.75°
R = 1.414 m
Diameter = 2 x R
D = 2 x 1.414
D = 2.828 m