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sleet_krkn [62]
3 years ago
14

You are called to the crime scene immediately and you begin your investigation at 2 PM. The first thing you do is take the tempe

rature of the body it is 84.4°F. You immediately walk over to the apartments thermostat and find that has been set at 68°F. The crime scene continues to be investigated wood samples taken and bagged. As everyone is finishing up, you take the temperature of the body again exactly 5 hours later and the temperature reads 79.6°F assume normal body temperature is 98.6°. What was the time of death? Use Newton’s Law if Cooling
Physics
1 answer:
adell [148]3 years ago
5 0

As per Newton's law of cooling we know that

\frac{\Delta T}{dt} = k(T_avg - T_s)

in 5 hours the body temperature becomes 79.6 from 84.4

while the surrounding temperature is given as 68 degree F

now from above formula

\frac{84.4 - 79.6}{5} = k (\frac{84.4 + 79.6}{2} - 68)

0.96 = k(14)

now let say the person died "t" time ago

now we will have

\frac{98.6 - 84.4}{t} = k (\frac{98.6 + 84.4}{2} - 68)

\frac{14.2}{t} = k(23.5)

\frac{14.2}{t} = \frac{0.96}{14}(23.5)

t = 8.8 hours = 9hours (approx)

so he died at approx 5 Am in  morning

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In the aftermath of an intense earthquake, the earth as a whole "rings" with a period of 54 minutes.
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The frequency of the oscillation in hertz is calculated to be 0.00031 Hz.

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So;

Period(T) = 54 minutes or 3240 seconds

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Learn more: brainly.com/question/14588679

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A Hertzsprung-Russel diagram is shown. Which stars are best characterized as having high temperatures and low luminosities?
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Read 2 more answers
Please show work : A particle with mass 2.00 μg and a charge of – 200 nC has a velocity of 3000 m/s in the x-direction. There is
irga5000 [103]

Answer:

 x =4.5 10⁴ m

Explanation:

To find the distance that the particle moves we must use the equations of motion in one dimension and to find the acceleration of the particle we will use Newton's second law

     m = 2.00 mg (1 g / 1000 ug) (1 Kg / 1000g) = 2.00 10-6 Kg

     q = -200 nc (1C / 10 9 nC) = -200 10-9 C

Let's calculate the acceleration

     F = ma

     F = q E

     a = qE / m

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     Vf² = Vo² -2 a x

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This is the distance the particule stop, after this distance in the field accelerates in the opposite direction of the initial

Second part

In this case Newton's second law is applied on the y axis

      F -W = 0

      F = w = mg

      E q = mg

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      E = 2.00 10⁻⁶ 9.8 / 200 10⁻⁹

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The direction of the field is such that the force on the particle is up, as the particle has a negative charge, the field must be directed downwards F = qE = (-q) E

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Gelneren [198K]

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