Available Answers

1. 1.

   Tick (√) the correct option:

   1. The shining streaks of light which are seen in a dark sky during a rainy day accompanied with thunder is termed as
      1. tsunami
      2. lightning
      3. earthquake
      4. none of the above
   2. Like charges
      1. always repel each other
      2. always attract each other
      3. can repel or attract each other depending on conditions
      4. can repel or attract each other depending on the quantity of charge
   3. A body may be charged by
      1. rubbing it against another body
      2. touching it with a negatively charged body
      3. touching it to a positively charged body
      4. All of the above
   4. The charge arrangement before a lightning bolt is
      1. lower end of clouds is negatively charged
      2. upper end of cloud is positively charged
      3. surface of earth below the clouds acquire positive charge
      4. all of the above
   5. 'Electrics' originated from Latin word 'Electron' which means
      1. amber
      2. proton
      3. sulphur
      4. glass
   6. The sound which we hear after lightning is termed as
      1. lightning
      2. thunder
      3. lightning rod
      4. none of the above
   7. The outermost layer of the earth is
      1. mantle
      2. crust
      3. outer core
      4. inner core
   8. The instrument used to measure seismic waves is called
      1. Manometer
      2. Caediograph
      3. Lectometer
      4. Seismograph
   9. The point on earth surface which lies directly above the focus of the earthquake is called
      1. hypocentre
      2. epicentre
      3. apicentre
      4. focus
   10. The magnitude of the earthquake is measured on a scale which is called
       1. Ricky's scale
       2. Victor's scale
       3. Seismic scale
       4. Richter scale
2. 2.

   Fill in the blanks:

   1. Silk acquires a _____________ charge when rubbed with a glass rod.
   2. Lightning generally strikes _____________ buildings.
   3. Opposite charges _____________ each other.
   4. When lightning strikes, it leaves behind a _____________ which is the cause of thunder.
   5. During lightning, a _____________ phone may be used.
   6. The intensity of an earthquake is measured on the _____________ scale.
   7. _____________ is a huge wave due to an earthquake occurring under the sea floor.
   8. Earthquakes are caused because of the motion of the _____________ plates in the outer crust of the earth.
   9. The shock waves of the earthquake are called _____________.
   10. An earthquake of magnitude 2-4 on Richter scale is a _____________ one.
3. 3.

   Find the odd one out:

   1. Thunder, lightning, sound, carpet.
   2. Copper, aluminium, iron, rubber.
   3. Seismologists, seimography, seismology, epicentre.
4. 4.

   Tick (√) the correct and cross (x) the wrong statement:

   1. The presence of lightning rods on top of buildings prevents a cloud with a static charge build up from releasing its charge to the building.
   2. If you put a lightning rod on top of your house but failed to ground it, it is likely that your home would be struck by lightning during a thunderstorm.
   3. You can use your PCs and other electrical gadgets while lightning.
   4. A car with windows closed is a safe place to take shelter while a thunderstorm.
   5. "The epicentre is the point from which an earthquake originates.
   6. Tsunamis originate on land.
   7. The Richter scale is logarithmic.
   8. The place nearest to the focus of an earthquake usually suffers destruction the most.
5. 5.

   How many types of electrical charges are there?

6. 6.

   What will happen if two like charges are brought closer?