HOW TO READ A CHAPTER

THE BASICS NEED TO BE STRONG TO ANSWER ANY QUESTION (ATLEAST MOST OF THE QUESTIONS!!) WHAT DO YOU MEAN BY BASICS? IT IS SOMETHING LIKE PREPARING FOR A 100M RACE. WHAT DO I REQUIRE? I NEED TO PRACTICE REGULARLY. I NEED TO KEEP MY BODY FIT I NEED TO HAVE GOOD EATING HABITS MORE IMPORTANTLY I HAVE TO LEARN TO RELAX!!! (i.e) I AM NOT WORRIED ABOUT WHAT OTHERS DO APPLYING THE SAME THEORY IN ACADEMICS, HOW SHOULD I PREPARE? I WILL GIVE A SAMPLE LESSON. (SAY) SIMPLE MACHINES

BASICS OF SIMPLE MACHINES WHAT IS A SIMPLE MACHINE? Try to visualise a crowbar with a fulcrum displacing a heavy object compared to manually displacing it. under that subject: what is force multiplier? what is speed multiplier? changing the direction of effort to convenient direction (e.g.) single fixed pulley TERMS RELATED TO SIMPLE MACHINE LOAD ---- A force required to be overcome (unit) EFFORT – Force applied by the machine to overcome the load (unit) What do you understand by the term “mechanical advantage”? it is the ratio of load to effort. (the book says) now ask these questions: when effort is more, where is the advantage? Isn't it a disadvantage? So why do we call it as a simple machine? VELOCITY RATIO --- Ratio of velocity of effort to velocity of load since the time moved is same, we modify the statement as ratio of distance moved by effort to that of load. DO I UNDERSTAND NOW WHAT IS VELOCITY RATIO????????

WORK INPUT ---- WORK DONE ON THE MACHINE --- (remember unit of work and the formula) WORK OUTPUT ---- WORK DONE BY THE MACHINE --- (remember unit of work and the formula) EFFICIENCY --- RATIO OF WORK DONE BY THE MACHINE TO WORK DONE ON THE MACHINE. ( imagine the physics teacher teaching you (work input) and your performance. Don’t worry, just joking!!! Another example – your preparation for the 100m race and the outcome UNDERSTANDING LEVERS What is a lever? REMEMBER MOMENTS WHEN YOU READ LAW OF LEVER (or) PRINCIPLE OF LEVERS. LOAD x LOAD ARM = EFFORT x EFFORT ARM WITH THIS AS BASIC TRY TO UNDERSTAND THE POSITION OF LOAD, FULCRUM AND EFFORT ON A LEVER. INSTEAD OF VISUALISING THE EXAMPLES GIVEN, CHECK THE IMAGES WITH THE HELP OF INTERNET.

FOR SOLVING PROBLEMS, WHAT DO I REQUIRE? KNOW LAW OF LEVER DRAW THE DIAGRAM LABELING LOAD, EFFORT AND FULCRUM AND FINALLY WRITING THE UNIT