Page 9 - Electrostatics 11 class
P. 9
Grade 11 © GC Shiba
Electroscope: It is a device which is used to detect
the charge present on a body. It is also used to
know the nature of the charge present on that body.
☻ Can a charged body attract on uncharged body?
Explain.
→ When a +vely charged body A is brought
near the uncharged body B, then the
opposite type charge is induced at the
nearer end and the similar type charge
(+ve) is induced at the remote end of the
body B. Now, there is attraction between
the opposite charges. In this way a charged
body attract the uncharged body.
☻ The tyres of airplane are made from a special rubber which is reasonably good
conductor of electricity, why?
→ During the motion of airplane on the runway, a large number of charges may
be accumulated which may cause explosion in the airplane. If the tyres are
made of a special rubber (good conductor), then the induced charges may flow
to the earth through them. They may reduce the explosion.
☻ More charge can be stored on a metal if it is highly polished than when its
surface is rough, explain.
→ We know, surface charge density =
In case of rough surface of a body, there are many projections. The surface
areas are less at these projections. So, the surface density of charge is greater
at these points. So, there are more possibility of leakage of charges and hence
such body contain lesser charge from a highly polished metallic body.
☻ The vehicles carrying inflammable fluid drag a chain along the ground, why?
→ During the motion of the vehicles on highway, due to the friction between the
tyres & the road, a large number of charges is accumulated in the body which
may cause explosion. With the help of a chain, the induced charge can be
flown to the ground.
☻ Sharp projections are avoided in machine, why?
→ In case of sharp projections due to the smaller surface areas, the surface
charge density is more. so, there is maximum leakage of charges at the
projections in machines. so, the sharp projections are avoided in machines.
9 Electrostatics
