1. Which of the following cannot be easily charged through friction?
(a) An artificial scale
(b) A rod of copper
(c)the inflated balloon
d) A cloth made of wool.
1. Which of the following cannot be easily charged through friction?
(a) An artificial scale
(b) A rod of copper
(c)the inflated balloon
d) A cloth made of wool.
Explanation:
A copper rod is the correct response (b)
Friction can easily charge only non-conducting materials. Copper is a substance with a high conductivity. A copper rod cannot thus be easily charged through friction.
2.When a silk cloth is used to rub a glass rod, the rod changes colour.
Both (a) and the fabric pick up a positive charge.
While the fabric is negatively charged,
(b) becomes positively charged.
(c) develops a negative charge, as does the fabric.
(d) turns negative while the fabric is positively charged.
2.When a silk cloth is used to rub a glass rod, the rod changes colour.
Both (a) and the fabric pick up a positive charge.
While the fabric is negatively charged,
(b) becomes positively charged.
(c) develops a negative charge, as does the fabric.
(d) turns negative while the fabric is positively charged.
Explanation:
The cloth has a negative charge, hence the correct solution is (b), which turns positively charged.
When two things come into contact with one another, they develop opposing charges. Conventional law states that the rod picks up a positive charge while the cloth picks up a negative charge
3. Write T against true and F against false in the following statements.
(a) Like charges attract each other. (T/F)
(b) A charged glass rod attracts a charged plastic straw. (T/F)
(c) Lightning conductors cannot protect a building from lightning. (T/F)
(d) Earthquakes can be predicted in advance. (T/F)
3. Write T against true and F against false in the following statements.
(a) Like charges attract each other. (T/F)
(b) A charged glass rod attracts a charged plastic straw. (T/F)
(c) Lightning conductors cannot protect a building from lightning. (T/F)
(d) Earthquakes can be predicted in advance. (T/F)
Explanation:
a) False: Contrary charges repel one another whereas similar charges attract one another.
b) True - The glass rod has a positive charge on its surface, compared to the negative charge on the surface of a charged plastic straw. They both draw attention to one another because unlike charges attract one another.
c) FALSE - When lightning strikes, a lightning conductor directly transfers the air charges to the earth. As a result, the structure is lightning-proof.
d) False - Although the causes of the earthquake are known, no instruments have been developed to identify them beforehand. Because of this, earthquakes cannot be foreseen.
4. On occasion in the cold, when putting off a sweater, a cracking sound is heard. Explain.
4. On occasion in the cold, when putting off a sweater, a cracking sound is heard. Explain.
Explanation:
Because to friction created by the sweater and the body when it is removed, the wool sweater charges up. There is a crackling sound as a result.
5.Describe why touching a charged object with our hand causes it to lose its charge.
5.Describe why touching a charged object with our hand causes it to lose its charge.
Explanation:
When we contact something charged, the charges are transferred via our bodies to the earth and the conductor loses its charge. Electric discharge is the term for this occurrence.
6. Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures 3 on this scale. Would it be recorded by a seismograph? Is it likely to cause much damage?
6. Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures 3 on this scale. Would it be recorded by a seismograph? Is it likely to cause much damage?
Explanation:
Richter scale is used to measure the destructive energy of an earthquake. The scale has a reading from 1 to 10.
An earthquake measuring 3 would be recorded by a seismograph.
The magnitude of scale 3 would not cause much damage. An earthquake of magnitude 5 is considered destructive in nature.
7. Suggest three ways we might safeguard ourselves from lightning.
7. Suggest three ways we might safeguard ourselves from lightning.
Explanation:
There are several techniques to shield ourselves against lightning.
(I )Always stay in a closed area, and if you're in a car, keep the windows closed and stay there until the lightning has passed.
(ii) Avoid touching any telephone cables, electrical wires, or metal pipes.
(iii)Never take a bath in running water; doing so could result in an electric shock..
8. Describe why a charged balloon repels a different charged balloon yet is drawn to a different charged balloon when they are both charged.
8. Describe why a charged balloon repels a different charged balloon yet is drawn to a different charged balloon when they are both charged.
Explanation:
The balloons are repulsed because their surface charge is of a similar kind. Due to the induction of charges, when a charged balloon is brought close to an uncharged balloon, the uncharged balloon picks up charges that are the opposite of those of the charged balloon. Uncharged balloon is drawn to charged balloon in the same way that charges of opposite polarity are attracted to one another.
9. Describe with the help of a diagram an instrument which can be used to detect a charged body.
9. Describe with the help of a diagram an instrument which can be used to detect a charged body.
Explanation:
It is composed of a metal rod with a metal disc attached to one end and two leaves of aluminium foil glued to the other end. To protect the leaves from ambient air, they are maintained in a conical flask that is corked.
The aluminium leaves move apart when a charged body makes contact with the metal disc because some charges are transferred to the leaves through the metal rod. This technique is termed charging via conduction. Because the charges on the leaves and the charged body are same in nature, the aluminium leaves resist one another. They would be drawn to one another if the body were not charged.
10. Assume an earthquake occurs while you are outside your home. What safeguards would you put in place to safeguard yourself?
10. Assume an earthquake occurs while you are outside your home. What safeguards would you put in place to safeguard yourself?
Explanation:
When an earthquake occurs, you should take the following precautions:
(a) Locate an open field, go there, and steer clear of any structures, trees, electric wires, or poles.
(b) If you are in a car, proceed to an open field without getting out.
11. A thunderstorm is expected to happen on a specific day, according to the weather service. Imagine you have an appointment that day. Would you carry a rain poncho? Explain.
11. A thunderstorm is expected to happen on a specific day, according to the weather service. Imagine you have an appointment that day. Would you carry a rain poncho? Explain.
Explanation:
No, you shouldn't have an umbrella with you while it storms. Lightning may strike during the thunderstorm, travelling from the cloud to the metal rod of the umbrella and potentially shocking the person holding it. So, it is dangerous to hold an umbrella when it is lightening.
