Answer:
Is it part of a computer?
Explanation:
Answer:
A battery changes chemical energy to <u>electrical</u> energy
A drum changes mechanical energy to <u>sound</u> energy
Explanation:
A battery is a device that stores chemical energy and converts it to electrical energy.
Beating a drum represents a mechanical to sound energy conversion.
Answer:
number of stages for the pump is 4
Explanation:
given data
water head Hm = 50 m
flow rate r = 0.1 m³/s
rotating N = 1800 rpm
to find out
optimal number of stages for the pump.
solution
we consider here specific speed does not exceed more than 82
so Ns formula will be
Ns = ![\frac{N\sqrt{r} }{H^{3/4}}](https://tex.z-dn.net/?f=%5Cfrac%7BN%5Csqrt%7Br%7D%20%7D%7BH%5E%7B3%2F4%7D%7D)
here Ns id 82 and N is rotating and r is flow rate
so
82 = ![\frac{1800\sqrt{0.1} }{H^{3/4}}](https://tex.z-dn.net/?f=%5Cfrac%7B1800%5Csqrt%7B0.1%7D%20%7D%7BH%5E%7B3%2F4%7D%7D)
so H = 13.23 m
so
number of stage n is
nH = Hm
n = ![\frac{50}{13.23}](https://tex.z-dn.net/?f=%5Cfrac%7B50%7D%7B13.23%7D)
n = 3.77 ≈ 4
so number of stages for the pump is 4
I think the answer is the third option