17. Convert the following compound sentences into complex sentences:
a) Speak the truth or I shall punish you.
b) She heard the news and set off at once.
c) She worked hard, therefore she succeeded.
18. Convert the following complex sentences into compound Sentences:
a) Although he is poor, he is honest.
b) He earns little though he is hardworking.
c) Unless you study regularly, you will make no progress.
Answers
Answer:
" DISCOVERY OF ELECTRON " Sir Joseph John Thomson was a British physicist was born in cheetham hill a suburb of Manchester on 18th December 1856. He was awarded by the Nobel prize in physics in 1906 for his work on the discovery of electron. Now ,before understanding how Thomson discovered the electron we have to know about what is (discharge tube,electrode and cathode rays)? Discharge tube - an electron tube which contains gas or vapor at low pressure and through which conduction takes place when a high voltage is applied. Electrode -conductors by which electrons flow through to generate a current. There are two types of electrodes- cathodes, and anodes. Cathode attracts the positively charged cations. Anode attracts negatively charged anions. Cathodes are also called negative electrode where as anodes are also called positive electrode. Cathode rays - Cathode rays are a beam of negatively charged electrons traveling from the negative end of an electrode to the positive end within a vacuum (where no air is present). Thomson explain the formation of cathode rays are as follows -; the gas taken in the discharge tube consists of atom and all the atoms contain electron where high electrical voltage is applied the electrical energy pushes out some of the electron from the atoms of the gas. These fast moving electrons form cathode rays the formation of cathode rays shows that one of the subatomic particle present in all the atoms is the negatively charged electron. By understanding all the above things the conclusion made by Thomson is-; Cathode rays consist of small negatively charged particles called electron.since all gases from cathode rays, it was included that all the atoms contain negatively charged particles called electron.. "Position and characteristics of electron" The electrons are located outside the nucleus in an atom . only hydrogen atom contains one electron all the other atoms contain more than one electron. And electron is usually represented by ( e-) e for electron and minus sign for negative charge.