Q.No.183: - When electrons pass through two parallel plates having opposite charges they are deflected towards the positively charged plate. What important characteristic of the electron can be inferred from this?

Q.No.183: - When electrons pass through two parallel plates having opposite charges they are deflected towards the positively charged plate. What important characteristic of the electron can be inferred from this?

Ans: - The shows that electrons have negative charge.

Q.No.182: - Give three reasons to support the evidence that cathode rays are negatively charged electrons.

Q.No.182: - Give three reasons to support the evidence that cathode rays are negatively charged electrons.

Ans: - 1) When cathode rays are created then they move to the anode of the discharge tube which shows that they are negatively charges.

2) When an electric field is applied in the discharge tube then cathode rays experiences an attractive force toward the positive plate of the applied electric field which also shows that they have negative charge.

3) By applying the magnetic field these rays stats moving in a circle. By applying Right Hand Rule we concluded that they have negative charge.

Q.No.171: - Explain why, a glass rod can be charged by rubbing when held by hand but an iron rod cannot be charged by rubbing, if held by hand?

Q.No.171: - Explain why, a glass rod can be charged by rubbing when held by hand but an iron rod cannot be charged by rubbing, if held by hand?

Ans: - Because iron is a conductor so when we rub it then electrons move within the conductor and did not become static on the other hand glass rod is an insulator and when we rub, it get charge on its surface and act like a charged body.

Q.No.168: - Rubber tires get charged from friction with the road. What is the polarity of the charge?

Q.No.168: - Rubber tires get charged from friction with the road. What is the polarity of the charge?

Ans: - When two materials rubbed together then they will transfer electron the one who get electrons become negatively charged and the other who lose this charge gets positive charge. When tires rubbed with road then road will transfer electrons to the tires hence tires get negative charge and the road who transfer electrons get positive charge.

Q.No.164: - In what direction will a positively charged particle move in an electric field?

Q.No.164: - In what direction will a positively charged particle move in an electric field?

Ans: - If the electric field is due to positive charge and we place a positive charge in this electric field then this charge will move along the electric field line or we can say that this charge will move in the direction of arrow head of the field. If the field is due to negative charge then the positive charge will move in the opposite direction i.e; towards the tails of the electric field.

Q.No.163: - How much negative charge has been removed from a positively charged electroscope if it has a charge of 7.5x10-11C?

Q.No.163: - How much negative charge has been removed from a positively charged electroscope if it has a charge of 7.5x10^-11C?

Ans: - Negative and positive charge are equal in magnitude. So, if electroscope has 7.5x10^-11C  of positive charge then it mean that 7.5x10^-11C of negative charge has been removed.