Answer:
A) a = 73.304 rad/s²
B) Δθ = 3665.2 rad
Explanation:
A) From Newton's first equation of motion, we can say that;
a = (ω - ω_o)/t. We are given that the centrifuge spins at a maximum rate of 7000rpm.
Let's convert to rad/s = 7000 × 2π/60 = 733.04 rad/s
Thus change in angular velocity = (ω - ω_o) = 733.04 - 0 = 733.04 rad/s
We are given; t = 10 s
Thus;
a = 733.04/10
a = 73.304 rad/s²
B) From Newton's third equation of motion, we can say that;
ω² = ω_o² + 2aΔθ
Where Δθ is angular displacement
Making Δθ the subject;
Δθ = (ω² - ω_o²)/2a
At this point, ω = 0 rad/s while ω_o = 733.04 rad/s
Thus;
Δθ = (0² - 733.04²)/(2 × 73.304)
Δθ = -537347.6416/146.608
Δθ = - 3665.2 rad
We will take the absolute value.
Thus, Δθ = 3665.2 rad
"Changing water salinity" is the most significant challenge for organisms that live in estuaries.
<u>Answer:</u> Option D
<u>Explanation:</u>
For estuaries, alkalinity levels are usually the maximum at a river's mouth where the ocean water falls for, and the minimum upstream where freshwater falls in. Although salinity vary throughout the tidal cycle. In estuaries, salinity rates usually decrease in spring as snow melt and rain raises the freshwater flow from streams and groundwater.
It influences the chemical environments within the estuary, especially the dissolved oxygen (DO) levels in the water. The level of oxygen that would get dissolved in water or its solubility get declined when the alkalinity rises.
D. all of the above
Hope this helps!
Answer:
Explanation:
Knowing that the formula for average velocity is:
Being said that, we know that the person's displacement is zero because it returns to its starting point
That means 
Answer:
a = 64 ft / s²
Explanation:
The force in a spring is given by Hooke's law
F = -k x
Let's use the initial data to calculate the spring constant
k = F / x
Reduscate to the English system
x = 3 in (1foot/12 in) =0.25 foot
k = 0.3 / 0.25
k = 1.2 lb / foot
Now we can use Newton's second law
F = ma
a = F / m
a = -k x / m
m = w / g
m = 0.3 / 32 = 0.009375
x= 6 in (1foot /12 in)= 0.5 foot
a = - 1.2 0.5 / 0.009375
a = 64 ft / s²
