Heat lost or gained, H = mc(θ₂ - θ₁)
Where m = mass, c = Specific heat capacity, θ₂= final temperature, θ₁ = initial temperature
m = 200g, c = 0.444 J/g°C, θ₁ = 22 °C (Since it was cooled).
H = 6.9 kj = 6.9 *1000J = 6900 J
6900 = 200*0.444* (θ₂ - 22)
6900/(200*0.444) = θ₂ - 22
77.70 = θ₂ - 22
θ₂ - 22 = 77.7
θ₂ = 77.7 + 22 = 99.7
So initial temperature before cooling ≈ 100°C . Option C.
The air pressure inside the balloon is: 0.1432 Pa
The formulas and procedures that we will use to solve this problem are:
Where:
- a = area of the sphere
- r = radius
- π = mathematical constant
- P = Pressure
- F = Force
- a = surface area
Information about the problem:
- r = 5.0 m
- F = 45 N
- 1 Pa = N/m²
- 1 N = kg * m/s²
- a=?
- P=?
Using the formula of the sphere area we get:
a = 4 * π * r²
a = 4 * 3.1416 * (5.0 m)²
a = 314.16 m²
Applying the pressure formula we get:
P = F/a
P = 45 N/314.16 m²
P = 0.1432 Pa
<h3>What is pressure?</h3>
It is a physical quantity that expresses the force applied on the area of a surface.
Learn more about pressure at: brainly.com/question/26269477
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The answer would be to research the need. This should have been done before the project began.
