Question 2 :
Goldsteins experiments which involved passing high voltage electricity through gases at very low pressure resulted in the discovery of:

Question 3 :
Which of the following is true for mass and charge of proton?

Question 4 :
Compared to the mass of lightest nucleus the mass of an electron is only:<br>

Question 10 :
The definitive experiments with cathode-ray tubes were done by ______ in 1879.

Question 13 :
Positronium is the name given to an atom -&#160;like combination formed between:

Question 14 :
The value of charge on the oil droplets experimentally observed were $-1.6 \times 10^{-19}$ and $-4 \times 10^{-19}$ coulomb. The value of the electronic charge, indicated by these results is:<br/>

Question 15 :
Which experiment is responsible for finding out the charge on an electron?

Question 17 :
Assertion: e/m ratio in case of anode ray experiment is different for different gases. Reason: The ion of gases formed after the ejection of electron are different if gas is different.

Question 18 :
Among the following, the correct statement about cathode ray discharge tube is:&#160;

Question 20 :
In an oil drop experiment, the following charges (in arbitary units) were found on a series of oil droplets:<br/>2.30 $\times$ 10$^{-15}$, 6.90 $\times$ 10$^{-15}$, 1.38 $\times$ 10$^{-14}$<br/>5.75 $\times$ 10$^{-15}$, 3.45 $\times$ 10$^{-15}$, 1.96 $\times$ 10$^{-14}$<br/>The magnitude of charge on the electron (in the same unit) is: