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A heart defibrillator passes 10.3 A through a patient's torso for 5.00 ms in an attempt to restore normal beating.(a) How much charge passed?(b) What voltage was applied if 492 J of energy was dissipated?KV(c) What was the path's resistance?ΚΩ(d) Find the temperature increase caused in the 8.00 kg of affected tissue. The specific heat of tissue is 3500 J/(kg. °C).°C

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a) The formula for calculating the quantity of charge is expressed as

Q = IT

where

Q is the quantity of charge

I is the current

T is the time

From the information given,

I = 10.3

T = 5 ms = 5 x 10^-3 s

Q = 10.3 x 5 x 10^-3

Q = 51.5 x 10^- 5 C

The quantity of charge passed is 51.5 x 10^- 5 C

b) The formula for calculating the energy is expressed as

E = I^2RT

where

R is the resistance

E is the energy

From the information given,

E = 492 J

Thus,

492 = 10.3^2 x R x 5 x 10^-3

R = 492/(5 x 10^-3 x 10.3^2)

R = 927.514 ohms

Voltage, V = IR

Voltage = 10.3 x 927.514

Voltage = 9553.398 V

We would divide by 1000. It becomes

Voltage = 9.553 KV

c) From the calculations,

Resistance = 927.514 ohms

We would divide by 1000. It becomes

Resistance = 0.93 ΚΩ

d) Let the temperature increase be t

mass of tissue, m = 8 kg

Specific heat of tissue = 3500 J/(kg. °C).

°C

The formula for calculating the quantity of heat is

H = mcθ

where

H is the quantity of heat

From the informtaion given,

H = 492

θ = t

Thus,

492 = 8 x 3500 x t

t = 492/(8 x 3500)

t = 0.018

The temperature increase is 0.018 degrees

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