Answer:
8.37×10⁻⁴ N/C
Explanation:
Electric Field: This is the ratio of electrostatic force to electric charge. The S.I unit of electric field is N/C.
From the question, the expression for electric field is given as,
E = F/Q.......................... Equation 1
Where E = Electric Field, F = force experienced by the charged balloon, Q = Charge on the balloon.
Given: F = 8.2×10⁻² Newton, Q = 9.8×10 Coulombs = 98 Coulombs
Substitute these values into equation 1
E = 8.2×10⁻² /98
E = 8.37×10⁻⁴ N/C
Hence the Electric Field of the charged balloon = 8.37×10⁻⁴ N/C
Answer: A. Work is done on the system and heat is transferred from the system for a net decrease in internal energy.
Explanation:
A refrigerator is a device which dispenses heat from the close system to a warmer area or in the surrounding. By dispensing the heat the internal temperature of the refrigerator drops. The system of refrigerator violates the second law of thermodynamics. As it performs the work to cool the region instead of heating the region. The work is done on the system and the internal energy decreases and the heat energy is liberated to the surrounding area. A refrigerator is an open system.
To solve this problem we will apply the concepts related to pressure, depending on the product between the density of the fluid, the gravity and the depth / height at which it is located.
For mercury, density, gravity and height are defined as



For the air the defined properties would be



We have for equilibrium that


Replacing,

Rearranging to find 


Therefore the elevation of the mountain top is 9400ft
The functions of angles are used to find unknown lengths or angles that can't be measured, in terms of known quantities. The trig functions of angles are ratios of lengths, so they're bare naked numbers without units.
The tension in the rope B is determined as 10.9 N.
<h3>Vertical angle of cable B</h3>
tanθ = (6 - 4)/(5 - 0)
tan θ = (2)/(5)
tan θ = 0.4
θ = arc tan(0.4) = 21.8 ⁰
<h3>Angle between B and C</h3>
θ = 21.8 ⁰ + 21.8 ⁰ = 43.6⁰
Apply cosine rule to determine the tension in rope B;
A² = B² + C² - 2BC(cos A)
B = C
A² = B² + B² - (2B²)(cos A)
A² = 2B² - 2B²(cos 43.6)
A² = 0.55B²
B² = A²/0.55
B² = 65.3/0.55
B² = 118.73
B = √(118.73)
B = 10.9 N
Thus, the tension in the rope B is determined as 10.9 N.
Learn more about tension here: brainly.com/question/24994188
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