Answer:
B. 0.014 kg
Explanation:
I GOT IT RIGHT IN MY ASSESMENT QUESTIONS
Answer:
7.875 ft/s
Explanation:
L = 15 ft
dx/dt = 3 ft/s
x = 9 ft
Let the top of ladder is coming down with the rate of dy/dt.
use Pythagorean theorem
L^2 = x^2 + y^2 .... (1)
Differentiate both sides with respect to t
0 = 2 x dx/dt + 2y dy/dt
x dx/dt = - y dy/dt
When, x = 9 ft then y = ? . Put this in equation (1)
15^2 = 9^2 + y^2
225 - 81 = y^2
y = 12 ft
So
dy/dt = - x (dx/dt) / y = - 9 (3) / 12 = - 9/4 ft/s
Let A be the area of the triangle
A = 1/2 (base)(height)
A = 1/2 (x y)
Differentiate both sides with respect to t
dA/dt = 0.5 (y dx/dt + x dy/dt)
dA/dt = 0.5 [ 12 (3) - 9 (9/4)]
dA/dt = 0.5(36 - 81 /4) = 31.5 / 4 = 7.875 ft/s
The climate<span> was generally warmer and more humid than today, probably because of very active volcanism associated with unusually high rates of seafloor spreading.
</span><span>The first placental mammals appeared at the beginning of the Cretaceous. The Cretaceous saw the rise and extinction of the toothed birds, Hesperornis and Ichthyornis. The earliest fossils of birds resembling loons, grebes, cormorants, pelicans, flamingos, ibises, rails, and sandpipers were from the Cretaceous.</span>
Answer:
The power radiated by the hawk is 0.452 Watt.
Explanation:
Given that,
Frequency = 50 Hz
Distance r=60 m
Level = 70 dB
We need to calculate the intensity
Using formula of intensity
Put the value into the formula
We need to calculate the power radiated by the hawk
Using formula of power
Put the value into the formula
Hence, The power radiated by the hawk is 0.452 Watt.
False they simple machines do not reduce the amount of work you do it would just reduce the amount of force you use.