The number is 500. 500×7=3,500.
Step-by-step explanation:
1. Perimeter = 2 ( 5+4) = <u>18 cm</u>
Area = 5 × 4 = <u>20 cm^2</u>
2. Perimeter = 2 (5+5) = <u>20 cm</u>
Area = 5 × 5 = <u>25 cm^2</u>
3. Cups of seed needed per sq. meter = Area of the rectangle backyard
= 6 × 7
= <u>42 </u><u>cups</u><u> </u><u>of</u><u> </u><u>seed</u>
4. Feet of fence needed = Perimeter of the Square garden
= 2(8+8)
<u>= 32 feet</u>
5. Perimeter of rectangular quilt = 2 (4+6) feet
= <u>20 feet</u>
6. Area of the room = 9 feet × 8 feet
= <u>72 feet^2</u>
Answer:
Power generated = 4.315 kW
Step-by-step explanation:
Given,
- speed of wind when enters into the turbine, V = 12 m/s
- speed of wind when exits from the turbine, U = 9 m/s
- mass flow rate of the wind, m = 137 kg/s
According to the law of conservation of energy
Energy generated = change in kinetic energy
Since, the air is exiting at same elevation. So, we will consider only kinetic energy.
Energy generated in one second will be given by,


=4315.5 J
= 4.315 kJ
So, energy is generated in one second = 4.315 kJ
Power generated can be given by,

And the energy is generated is already in per second so power generated will be 4.315 kW.