This room is called Substation
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

where
is the air density, v = 8.89 m/s is the wind speed, A is the swept area and
is the efficiency



The swept area is a circle with radius r being the blade length



Answer: 8400 J
Explanation:
The formula referenced in the question is:
Where:
is the thermal energy
is the mass of the water sample
is the specific heat capacity of water
is the variation in temperature
Solving:
This is the thermal energy released
Answer:
1000 Joules per second.
Explanation:
To lift that much grass 5 meters higher than it was before the tractor did work that is the product of the (force needed to overdo gravity) and (displacement):

Power is work over the amount of time:

Mostly GPE and a little KE since the ball is high up (GPE) and it's also moving (KE) but not as much as it had when you first threw it