<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
Answer:
F = 1200 N
General Formulas and Concepts:
<u>Forces</u>
Newton's Second Law of Motion: F = ma
- F is force (in N)
- m is mass (in kg)
- a is acceleration (in m/s²)
Explanation:
<u>Step 1: Define</u>
<em>Identify variables</em>
<em>m</em> = 300 kg
<em>a</em> = 4 m/s²
<u>Step 2: Find Force</u>
- Substitute in variables [Newton's Second Law of Motion]: F = (300 kg)(4 m/s²)
- Multiply: F = 1200 N
Topic: AP Physics 1 - Algebra Based
Unit: Forces
Answer:
d. In dc steady state conditions, the voltages across the capacitors are constant and the currents through the capacitance are zero. The current through the inductors are constant and the voltage across the inductances are zero.
Explanation:
The current through a capacitor is given by i = CdV/dt where C = capacitance of capacitor and V = voltage across capacitor. At steady state dV/dt = 0 and V = constant. So, i = CdV/dt = C × 0 = 0.
So, in dc steady state, the voltage across a capacitor is constant and the current zero.
The voltage across an inductor is given by V = Ldi/dt where L = inductance of inductor and i = current through inductor. At steady state di/dt = 0 and V = constant. So, V = Ldi/dt = L × 0 = 0.
So, in dc steady state, the voltage across an inductor is zero and the current constant.
So,<u> In dc steady state conditions, the voltages across the capacitors are constant and the currents through the capacitance are zero. The current through the inductors are constant and the voltage across the inductances are zero.</u>
<u>The answer is d.</u>