Answer : First of all, to harness the solar energy and utilize it for the decomposition of water to make hydrogen fuel cell seems to be easy but practically it has many hurdles in its way. It might not work well, when the days would not be sunny. Also, the production of hydrogen fuel would require decomposing water which may need a high energy of activation, which would be more than the energy that will be produced from the fuel cell.
Answer:
a
Explanation:
heat is energy, energy cannot be made or destroyed but transferred
Vector ' W ' best and there ya go
Answer:
Y = V / f where Y equals wavelength
4 Y1 = V / f1 for a closed pipe the wavelength is 1/4 the length of the pipe
2 Y2 = V / f2 for the open pipe the wavelength is 1/2 the length of the pipe
Y1 / Y2 = 2 = f2 / f1 dividing equations
f2 = 2 f1
the new fundamental frequency is 2 * 130.8 = 261.6
(The new wavelength is 1/2 the original wavelength so the frequency must double to produce the same speed.
U=RI Ohm's law
then R=U/I
=120/0.08
=2250Ω
hope this helps you