In the following three arrangements each resistor has the same resistance r. rank the equivalent resistances of the arrangements in descending order (largest first) 15. the peak value of the ac current in a circuit is 6.0 a, and peak value of the ac voltage applied to the circuit is 4.1 v. what is the average power delivered to the circuit? 16. the temperature coefficient of resistivity or a material is 0.0035 (c^o)^-1. by how much at does the temperature of a wire made from this material have to change, in order that the resistance of the wire doubles?

Explanation:

15 ) Current_rms = Peak current / √2

= 6 / √2

= 4.24 A

Voltage_rms = 4.1 / √2

= 2.9 v

Average power = Voltage_rms x Current_rms

= 2.9 x 4.24

= 12.3 W

16 ) R₂ = 2R₁

Resistance of a material changes due to change in resistivity of material .

So resistivity ρ₂ will also be twice resistivity ρ₁

ρ₂  = 2ρ₁

2ρ₁ = ρ₁ ( 1 + .0035 t ) where t is rise in temperature.

1 = .0035 t

t = 1 / .0035

= 285.7 ⁰ C

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =