Answer:
0.67 s
Explanation:
This is a simple harmonic motion (SHM).
The displacement,
, of an SHM is given by

A is the amplitude and
is the angular frequency.
We could use a sine function, in which case we will include a phase angle, to indicate that the oscillation began from a non-equilibrium point. We are using the cosine function for this particular case because the oscillation began from an extreme end, which is one-quarter of a single oscillation, when measured from the equilibrium point. One-quarter of an oscillation corresponds to a phase angle of 90° or
radian.
From trigonometry,
if A and B are complementary.
At
, 


So

At
, 





The period,
, is related to
by

Explanation:
Given that, a hiker walls 9.4 miles at an angle of 60 degrees south of west. We need to find the west and south components of the walk.
From the attached figure, it is clear that, the west component of the walk is given by :

The south component of the walk is given by :

So, the west and south components of the walk are 4.7 miles and 8.14 miles respectively. Hence, this is the required solution.
When light passes from one medium to another at an angle, it may refract, or bend, according to Snell's law:
n₁sin(θ₁) = n₂sin(θ₂)
n₁ = index of first medium, θ₁ = angle of incidence, n₂ = index of second medium, θ₂ = angle of refraction
Given values:
n₁ = 1.33 (water), θ₁ = 45.0°, θ₂ = 40.3°
Plug in and solve for n₂:
1.33sin(45.0°) = n₂sin(40.3°)
n₂ = 1.454
I looked up this value on the HyperPhysics indices of refraction table... The index we calculated is closest to 1.46, which is that of fused quartz.
H's result was one dead flower ... not surprising ... stuck in a dark room = no photosynthesis = no growth = death.
H loses is "control" part of his "experiment".
Q gives no idea the colour of H's flowers in expt.
H "shows" that a watered plant in sunlight with a bit of fetilizer tends to grow. He could have had a look outside at a garden to see that.
improvement by not killing the "control" plant. put it side by side with the test plant, so both get the photo stuff. Then measured fertilizer in test plant, and same water minus fert in control.
As for the colour I've no idea.