Answer:
Explanation:
The rms voltage = 140/√2 = 140/1.414 = 99 V.
Reactance of inductor = wL = 2 X 3.14 X 100 X 113 X 10⁻³ =70.96 ohm.
Total resistance in terms of vector = 50+70.96j
j is imaginary unit number
Magnitude of this resistance = √ 50² + 70.96² = 86.80 ohm
current in resistance (rms) ( I ) = 99/86.80 = 1.14 A.
Power dissipated in resistor = I² R = 1.14 X 1.14 X 50 = 65 W( approx)
Answer:
2000 ohms
Explanation:
Resisters in series just add.
Rt = R1 + R2 + R3
R1 = 650 ohm
R2 = 350 ohm
R3 = 1000 ohm
Rt = 650 + 350 + 1000
Rt = 2000 ohms.
The boiling point of ethanol is at 78.37°C. So, the energy must include sensible heat to raise 19°C to the boiling point and latent heat to change liquid to gas. The equation would be
Energy = Sensible heat + Latent heat
Energy = mCpΔT + mΔH
For ethanol,
Cp = 46.068 + 102,460T - 139.63T² - 0.030341T³ + 0.0020386T⁴ J/kmol·K
ΔH = 38,560 J/mol
Integrate the Cp expression to determine CpΔT:
CpΔT = ∫₂₉₂³⁵²(46.068 + 102,460T - 139.63T² - 0.030341T³ + 0.0020386T⁴ )dT
The upper limit is (78.37+273) = 352 K, while the lower limit is (19 + 273) = 292.
CpΔT = 2384857192 J/kmol·K
2,000 J = m(2384857192 J/kmol)(1 kmol/1000 mol) + m(38,560 J/mol)
m = 8.253×10⁻⁴ moles of ethanol
Since the molar mass of ethanol is 46.07 g/mol,
Mass = (8.253×10⁻⁴ mol)(46.07 g/mol)
Mass = 0.038 g ethanol
Answer: D. the distance between the highest points of consecutive waves
Explanation:
The wavelength of a wave is defined as the <em>distance traveled by a periodic perturbation that propagates through a medium in a given time interval</em>. It is usually represented by
and can be calculated if the frequency of the wave is known, since there is an inverse relationship between both.
In the specific case of a periodic sine wave (which is the way in which a wave is usually represented graphically) the wavelength can be determined as the distance between two consecutive maxima of the disturbance.
Therefore, the correct option is D.
The combined system of you + elevator has two forces, a combined force of gravity and the tension in the cable. Consider the normal force acting on you from the elevator: N = mg if the elevator is at rest or moving at constant velocity. N = mg + ma if the elevator has an upward acceleration.