5. Some Natural Phenomena.

5. Some Natural Phenomena.

12 Maths Exercise Solutions

Which of the following cannot be charged easily by friction?（ ）
A. A plastic scale
B. A copper rod
C. An inflated balloon
D.  A woollen cloth.
5.8 Exercises., Question No.1
Which of the following cannot be charged easily by friction?（ ）
A. A plastic scale
B. A copper rod
C. An inflated balloon
D.  A woollen cloth.
When a glass rod is rubbed with a piece of silk cloth the rod（ ）
A. and the cloth both acquire positive charge.
B. becomes positively charged while the cloth has a negative charge.
C. and the cloth both acquire negative charge.
D. becomes negatively charged while the cloth has a positive charge.
5.8 Exercises., Question No.2
When a glass rod is rubbed with a piece of silk cloth the rod（ ）
A. and the cloth both acquire positive charge.
B. becomes positively charged while the cloth has a negative charge.
C. and the cloth both acquire negative charge.
D. becomes negatively charged while the cloth has a positive charge.
State whether the following statement is True or False.
Earthquakes can be predicted in advance.___
5.8 Exercises., Question No.3
State whether the following statement is True or False.
Earthquakes can be predicted in advance.___
State whether the following statement is True and False.
Like charges attract each other.___
5.8 Exercises., Question No.4
State whether the following statement is True and False.
Like charges attract each other.___
State True or False:
A charged glass rod attract a charged plastic straw.___
5.8 Exercises., Question No.5
State True or False:
A charged glass rod attract a charged plastic straw.___
State whether the statement is True or False:
Lightning conductor cannot protect a building from lightning.___
5.8 Exercises., Question No.6
State whether the statement is True or False:
Lightning conductor cannot protect a building from lightning.___
Explain why a charged body loses its charge if we touch it with our hand.
5.8 Exercises., Question No.7
Explain why a charged body loses its charge if we touch it with our hand.
Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures on this scale. Would it be recorded by a seismograph? Is it likely to cause much damage?
5.8 Exercises., Question No.8
Name the scale on which the destructive energy of an earthquake is measured. An earthquake measures on this scale. Would it be recorded by a seismograph? Is it likely to cause much damage?
Suggest three measures to protect ourselves from lightning.
5.8 Exercises., Question No.9
Suggest three measures to protect ourselves from lightning.
Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another charged balloon?
5.8 Exercises., Question No.10
Explain why a charged balloon is repelled by another charged balloon whereas an uncharged balloon is attracted by another charged balloon?