How many try did it take thomas Edison to finsh the light bulb?

Who discovered wind energy? If you slide the sliding weight on the front beam until what is matched up on a triple beam balance? Why electricity is not an energy? What is the energy transferred from a hotter object to a cooler one is referred to as what? Which term is the best description of the surface of a plane mirror? What causes an electrical flash over? How is one type of wave distinguished from another? Do you fall faster as you go down? What do humans use to sense acceleration? What is the product of force and its lever distance called? Why is uniform circular motion an accelerated motion? What is the bending of light because of change in its velocity? What is a sentence using the word radiate? Does oil increases friction? What invention lets you walk through walls? What can carry energy from one place to another by periodic motions? What will cause a decrease in a gas pressure in a closed container? What is the scientific definition of a buoyant force? What are the action reaction forces of a falling object in a vacuum? Does thin wires have high or low resistance?

How many try did it take thomas Edison to finsh the light bulb?