Suppose you left a 100-W light bulb on continuously for one month. If the electricity generation and transmission efficiency is 30%, how much chemical energy (in joules) was wasted at the power plant for this oversight? If the fuel consumption for one meal in Cambodia using a kerosene wick stove is 6 MJ (1 MJ = 1,000,000 joules), how many equivalent meals could be cooked with this wasted energy.
Answers
The wasted chemical energy be "8.64 × 10⁸ J" and the equivalent meals could be cooked be "144".
Chemical energy
According to the question,
Bulb power, P = 100 W
Time, t = 1 month or,
= 1 × 30 × 24
= 720 h
Efficiency, η = 30% or,
= 0.30
Fuel consumption, E = 6 MJ or,
= 6 × 10⁶ J
Energy consumed be:
→ = P × t
By substituting the values,
= 100 × 720
= 72 kWh
Wasted energy be:
→ =
=
= 240 kWh or,
= 240 × 3.6 × 10⁶
= 8.64 × 10⁸ J
and,
The no. of meals be:
→ N =
= 144 meals
Thus the answers above are correct.
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Answer:
a
b
Explanation:
From the question we are told that
The power rating of the bulb is P = 100 W
The duration is t = 1 month = 1 * 30 * 24 = 720 h
The efficiency is
The fuel consumption for one meal is
Generally the energy consumed by the bulb is mathematically represented as
=>
=>
Generally the energy generated at the power plant that was wasted by the bulb is mathematically represented as
=>
=>
Converting this value to Joules
Generally the number of means that would be cooked is
=>
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Answer:
An electric current passing through a coil of wire gives a strong form of magnetism called electromagnetism. When the electric current passes through a single straight piece of wire the electromagnetism is weak.
Explanation:
Final answer:
Passing an electric current through a coil of wire generates a magnetic field. The strength of this field can be modified by changing the amount of current or the number of turns in the coil.
Explanation:
When an electric current passes through a coil of wire, as opposed to a straight piece, it creates a magnetic field around the coil. This is the principle behind electromagnets and many electrical appliances we use on a daily basis. The strength of the magnetic field depends on the amount of current and the number of turns in the coil. For example, the more turns the wire has, the stronger the magnetic field.
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Answers
Answer: 38.5rad/s
Explanation: The calculations can be viewed on the image attached below. Thanks
Answers
Answer:
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Explanation:
So like optical telescopes capture light waves, introduce it to concentrate, enhance it, as well as make it usable through different instruments via study, so radio telescopes accumulate weak signal light waves, introduce that one to focus, enhance it, as well as make this information available during research. To research naturally produced radio illumination from stars, galaxies, dark matter, as well as other natural phenomena, we utilize telescopes.
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Answers
Answer:
0.157 V
Explanation:
Parameters given:
Number of turns, N = 1207
Diameter of coil = 20 cm = 0.2 m
Radius of coil, r = 0.2/2 = 0.1 m
Magnetic field strength, B =
Time interval, t = 10 ms =
The average EMF induced in a coil due to a magnetic field is given as:
EMF =
where A = Area of coil
A = π
Therefore, EMF will be:
5.0 kg
B
25 N
C
49 kg
D
49 N
Answers
The weight of a 5.0-kilogram object at the surface of Earth is 49 N. Hence, option (C) is correct.
What are mass and weight?
Mass is a fundamental quantity in physics and the most fundamental attribute of matter. Mass can be defined as the amount of matter contained in a body. Kilogram is the SI unit of mass (kg).
A body's mass does not alter at any time. Only in severe instances where a massive amount of energy is provided or removed from the body.
The force of gravity acting on a body is measured by weight. The weight formula is as follows: w = mg. Because weight is a force, it has the same SI unit as force; the SI unit of weight is Newton (N).
The weight of the object is = 5.0 × 9.8 N
= 49.0 N.
Hence, option (B) is correct.
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Answer:
49 N (d)
Explanation:
w= mg = 5 kg * 9.8 m/s^2 = 49 N
Answers
Answer:
a)2.46 %
b)For 1 :101.52 %
For 2 : 99.08 %
c)100..4 %
Explanation:
Given that
g₁ = 9.96 m/s²
g₂ = 9.72 m/s²
The actual value of g = 9.8 m/s²
a)
The difference Δ g = 9.96 -9.72 =0.24 m/s²
b)
For first one :
For second :
c)
The mean g(mean )
a)2.46 %
b)For 1 :101.52 %
For 2 : 99.08 %
c)100..4 %
Final answer:
The percent difference between the two measurements is 2.44%. The percent error for the first measurement is 1.63%, and for the second measurement is 0.82%. The percent error of their mean is 0.41%.
Explanation:
In physics, the percent difference is calculated by subtracting the two values, taking the absolute value, dividing by the average of the two values, and then multiplying by 100. Therefore, the percent difference between the two measurements 9.96m/s² and 9.72m/s² is:
|(9.96-9.72)|/((9.96+9.72)/2)*100 = 2.44%
The percent error involves taking the absolute difference between the experimental value and the accepted value, divided by the accepted value, then multiplied by 100. So, the percent error for the two measurements with accepted value of 9.80m/s² are:
For 9.96m/s²: |(9.96-9.80)|/9.80*100 = 1.63%
For 9.72m/s²: |(9.72-9.8)|/9.8*100 = 0.82%
The percent error of the mean involves doing the above but using the mean of the experimental measurements:
|(Mean of measurements - Accepted value)|/Accepted value * 100 |(9.96+9.72)/2-9.8|/9.8*100 = 0.41%
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