Answer:
1454.54 kJ/h or 0.404 kW
Explanation:
Provided:
The heat being removed by the refrigerator is 800 kJ/h.
The refrigerator's coefficient of performance (COP) is 2.2.
Since the refrigerator operates for one-fourth of the time,
it effectively removes heat, Q = 
= 3200 kJ/h.
Next, the power consumed by the refrigerator during its operation is calculated as:
= 
.
= 1454.54 kJ/h
Thus, the fridge uses 1454.54 kJ/h
or 0.404 kW (given 1 kW = 3600 kJ/h).
Answer:
A. a collection of mathematical topics that are pertinent to basic physics.
Explanation:
The physics primer is not the same as the comprehensive online mathematics textbooks. Instead, it comprises topics in mathematics that challenge students and are noteworthy.
Therefore, it can be understood as the framework for resolving physics-related problems. Thus, mathematical skills are integral within physics courses, serving as a preparatory tool for success.
In summary, it represents a compilation of mathematical subjects that are relevant to foundational physics.
Answer:
ΔL = MmRgt / (2m + M)
Explanation:
The system starts from rest, so the change in angular momentum correlates directly to its final angular momentum.
ΔL = L − L₀
ΔL = Iω − 0
ΔL = ½ MR²ω
To determine the angular velocity ω, begin by drawing a free body diagram for both the pulley and the block.
For the block, two forces act: the weight force mg downward and tension force T upward.
For the pulley, three forces are present: weight force Mg down, a reaction force up, and tension force T downward.
For the sum of forces in the -y direction on the block:
∑F = ma
mg − T = ma
T = mg − ma
For the sum of torques on the pulley:
∑τ = Iα
TR = (½ MR²) (a/R)
T = ½ Ma
Substituting gives:
mg − ma = ½ Ma
2mg − 2ma = Ma
2mg = (2m + M) a
a = 2mg / (2m + M)
The angular acceleration of the pulley is:
αR = 2mg / (2m + M)
α = 2mg / (R (2m + M))
Finally, the angular velocity after time t is:
ω = αt + ω₀
ω = 2mg / (R (2m + M)) t + 0
ω = 2mgt / (R (2m + M))
Substituting into the previous equations gives:
ΔL = ½ MR² × 2mgt / (R (2m + M))
ΔL = MmRgt / (2m + M)
E_total = 5.8 x 10⁴ N/C
Explanation: To determine the electric field at specified points, we must calculate the vectors individually for each charge and sum them. The electric field caused by each charged conductive sheet can be derived via Gauss's law with the understanding of scalar products between the electric field and relevant surfaces.
