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The draft velocity of electrons, which refers to their average velocity in a conductor in response to an electric field, is typically very small compared to the speed of light. While the speed of electrons can vary depending on the material and conditions, in most conductors, electrons move relatively slowly, on the order of millimeters per second or less. In comparison, the speed of light in vacuum is approximately 299,792 kilometers per second.

Therefore, the correct answer is:

very small as compared to the speed of light

The resistance of the human body can vary depending on factors such as skin moisture, contact area, and individual characteristics. However, a typical value for the resistance of dry human skin is around 100,000 ohms (100 kΩ), while the resistance of wet skin can be significantly lower, around 1,000 ohms (1 kΩ) or less. Therefore, the resistance of the human body is approximately:

1000 ohms

The substances which have a large number of free electrons and offer a low resistance are called conductors. Conductors allow electric current to flow easily due to the presence of these free electrons, which can move throughout the material. Metals such as copper and aluminum are common examples of conductors.

Therefore, the correct answer is:

conductors

Among the materials listed, copper is not a poor conductor; in fact, it is an excellent conductor of electricity. Cast iron, carbon, and tungsten are relatively poor conductors compared to copper.

Therefore, the correct answer is:

Copper

To replace a 1500 Ω resistor using several 1000 Ω resistors, you can combine them in series and parallel combinations to achieve the desired resistance.

Here's one way to achieve a resistance of 1500 Ω:

1. Connect one 1000 Ω resistor.
2. Connect another 1000 Ω resistor in parallel with the first one. This combination will give you an effective resistance of \( \dfrac{1000 \times 1000}{1000 + 1000} = 500 \) Ω.
3. Connect the 500 Ω combination in series with a third 1000 Ω resistor.

This arrangement effectively creates a combination of resistors that results in a total resistance of 1500 Ω.

Therefore, the correct answer is:

two in parallel and one in series

The value of the dielectric constant for a vacuum is approximately 1.

Bakelite
A thermosetting phenol formaldehyde resin that is heat-resistant and electrically nonconductive. Bakelite is used in electrical insulators, radio and telephone casings, and other products

1 volt/metre is equivalent to 1 newton/metre.

One volt is equivalent to one joule/coulomb.

The total deficiency or excess of electrons in a body is known as charge.