Presentation on theme: "Chapter 9 The Passive Voice The range of transmission frequencies that can be carried on a communications line is referred to as the bandwidth of the line."— Presentation transcript:
Chapter 9 The Passive Voice The range of transmission frequencies that can be carried on a communications line is referred to as the bandwidth of the line. Bandwidth is a very important ingredient in data communications because the capacity (stated in bits per second) of a communications path is dependent on the bandwidth of the path. If the telephone channel were increased from a bandwidth of 3 kilohertz (kHz) to 20 kHz, it could carry all the characteristics of the voice. This also holds true for transmitting data; a better data transmission rate can be achieved with a greater bandwidth.
9.1 The Passive Voice Converted Into the Active Voice 9.1.1 The Original Subject Unchanged While a current is flowing through a wire, the latter is being heated. The ripple is very much reduced by the double filtering action. The definitions of the trigonometric functions were given in Section 3-2.
Sometimes the communications would be seriously disturbed by solar spots. These problems must be solved before a chain reaction starts. The liquid fuel rocket is continuously improved. If the amount of positive and negative charges is varied, the electron stream can be made to bend up or down in varying amounts.
9.1.2 Changing Original Subject Into Object A knowledge of statistics is required by every type of scientist for the analysis of data. Earthquakes seem less easy to be controlled by man than weather. Mechanical energy can be changed back into electrical energy through a generator.
9.1.3 Adding a Proper Subject to Make the Chinese Version Smooth At that time it was found that an electric current can produce the heating effect. Silver is known to be the best conductor. When one of the charged bodies has a polarity opposite to the other, there is said to be a difference of potential between them.
9.2 The Passive Structure Converted Into a Sentence Without a Subject If a source of e.m.f is applied to a closed circuit, the current will be found to flow continuously in the circuit. Attempts were made to develop a new technique for breeding rice variety. In this case, a 2-mV signal may be applied to the input of the amplifier. A film of oil is inserted between the sliding surfaces of a bearing.
If a 10-kilogram box is lifted one meter, the work done is 10-kilogram-meter. With all its advantages the accuracy of the new dating method using radioactive C-14 cant be blindly trusted.
9.3 The Passive Structure Remaining Unchanged Besides voltage, resistance and capacitance, an alternating current is also influenced by inductance. Radars have been used extensively for mapping geological structures and features. Each dot of light is translated by the camera tube into an electronic signal. Sound is carried by air, and without air there can be no sound.
9.4 Rendering Into Chinese by Using … We assume that this condition is fulfilled in all that follows. Resistance is measured in ohms. In actual practice separate subtractors are not used. Some plastics have been discovered by accident. Air, as well as water, is needed to make plants grow. Electromagnetic waves carry the energy which is received from the current flowing in the conductor.