I believe it is A. Just don't hold me down on that. :D
Explanation:
10
/9 Ω
potential difference across the cell in open circuit is the emf of the cell.
Hence, emf E=2.2V
when, circuit is closed, potential difference across cell is given by V=E−Ir
And,
I= E/
R+r
Hence, V= E− Er/
R+r
⟹ V= ER/
R+r
⟹ 1.8= 2.2×5
/5+r
⟹9+1.8r=11
⟹ r= 2/ 1.8 Ω
⟹ r= 10/9 Ω
Answer:
wavelength= 5.35×10cm=0.535m
f= 16000hz
v= wavelength × f= 0.535×16000=8560m/sec
