200 Hz = 200 cycles per sec
<span>1 cycle, the period = 1/200 = 0.005 seconds, or 5 milli seconds.</span>
Hi
The answer to this question is B. Reaction
A = (v - u) / t
a = acceleration
v = final velocity
u = initial velocity
t = time
45 = (v - 300) / 10
45 × 10 = v - 300
450 + 300 = v
v = 750 m/s
Hope this helps!
P.S. Let me know if you need an explanation
Answer:
4.1 m
Explanation:
10 kW = 10000 W
20mi/h = 20*1.6 km/mi = 32 km/h = 32 * 1000 (m/km) *(1/3600) hr/s = 8.89 m/s
The power yielded by the wind turbine can be calculated using the following formula
![P = \frac{1}{2} \rho v^3 A C_p](https://tex.z-dn.net/?f=P%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20%5Crho%20v%5E3%20A%20C_p)
where
is the air density, v = 8.89 m/s is the wind speed, A is the swept area and
is the efficiency
![10000 = 0.5 * 1.2 * 8.89^3 * A * 0.45](https://tex.z-dn.net/?f=10000%20%3D%200.5%20%2A%201.2%20%2A%208.89%5E3%20%2A%20A%20%2A%200.45)
![10000 = 190A](https://tex.z-dn.net/?f=10000%20%3D%20190A)
![A = 10000 / 190 = 52.7 m^2](https://tex.z-dn.net/?f=A%20%3D%2010000%20%2F%20190%20%3D%2052.7%20m%5E2)
The swept area is a circle with radius r being the blade length
![\pi r^2 = A = 52.7](https://tex.z-dn.net/?f=%5Cpi%20r%5E2%20%3D%20A%20%3D%2052.7)
![r^2 = 52.7 / \pi = 16.79](https://tex.z-dn.net/?f=r%5E2%20%3D%2052.7%20%2F%20%5Cpi%20%3D%2016.79)
![r = \sqrt{16.79} = 4.1 m](https://tex.z-dn.net/?f=r%20%3D%20%5Csqrt%7B16.79%7D%20%3D%204.1%20m)
Answer:
Ice is water in solid phase, in this phase, the particles are very close together and relatively in fixed positions.
As the temperature starts to increase (thermal energy), also does the kinetic energy of the particles (so we have a change from thermal energy to kinetic energy), so they start to move "more", and the position of the particles starts to be less "fixed". There is a point where the particles have enough energy, and this point is where the phase of the water changes from solid to liquid phase (the fusion point). After this point the water can not hold his shape, and takes the shape of the container where it is.