Warning: Cannot modify header information - headers already sent by (output started at /home/content/70/7481070/html/appsrc/doyouknow.php:18) in /home/content/70/7481070/html/header.php on line 20

Warning: Cannot modify header information - headers already sent by (output started at /home/content/70/7481070/html/appsrc/doyouknow.php:18) in /home/content/70/7481070/html/header.php on line 21
cExams.net
Do You Know
Questions & Answers on General Knowledge.

Question:
What causes a dropped ball to bounce?
Answer:
When you lift a ball off the floor, you transfer energy to it. This energy is stored in the gravitational force between the ball and the earth and is called gravitational potential energy. When you release the ball, its weight makes it accelerate downward and its gravitational potential energy gradually becomes kinetic energy, the energy of motion. When the ball hits the floor, both the ball's bottom surface and the floor's upper surface begin to distort and the ball's kinetic energy becomes elastic potential energy in these two distorted surfaces. The ball accelerates upward during this process and eventually comes to a complete stop. When it does, most of the energy that was initially gravitational potential energy and later kinetic energy has become elastic potential energy in the surfaces. However, some of the original energy has been converted into thermal energy by internal frictional forces in the ball and floor. The distorted ball and floor then push apart and the ball rebounds into the air. Some or most of the elastic potential energy becomes kinetic energy in the ball, and the rising ball then converts this kinetic energy into gravitational potential energy. But the ball doesn't reach its original height because some of its original gravitational potential energy has been converted into thermal energy during the bounce.
--- >>>
More Questions:
  • Please explain the forces that allow one team to win a Tug-O-War contest.
  • Where can I find Africa on the globe?
  • What's a rip tide?
  • Who was the first African American in space?
  • What happens to the current when it "stops"?
  • What happens when you accidentally microwave a metal fork, and then eat the food it was in?
  • Why do wives call money from their husbands “pin money”?
  • What is smog?
  • Why does water react in a violent and dangerous way when overheated in a microwave oven?
  • What is athletics?
  • Who discovered America?
  • Aren't dinosaurs from the Jurassic period in time?
  • How is steel used in skyscrapers?
  • Where is the wettest place in the world?
  • Why is gossip called “scuttlebutt”?
  • Who are Asia's neighbours?
  • Can penguins walk?
  • How can temperatures be taken accurately and so quickly in the ear?
  • Can we create an invisible wall of electromagnetic fields?
  • What causes the colors in the aurora borealis?
  • Why is someone with a lot of nerve referred to as being “full of moxie”?
  • What is a dingo?
  • Why are tires filled with air instead of something less likely to go flat?
  • What’s a cobweb?
  • Is there any new clue on how life began?
  • Benefits of Hair Straightening
  • Class 9 - Vocabulary
  • Tips to Remove Pimples on Face
  • Durga Puja
  • LosAngeles
  • Handmade Valentines Day Cards

  • The Best New Cars

    Audi A3

    The 2015 Audi A3 sedan 2.0t quattro features cuttingedge technology, bold, handsome styling and the brilliant TFSI turbo four cylinder engine, all wrapped in a stiff, capable chassis. It accelerates quickly while still returning up to 33 mpg on the highway.


    Chourishi Systems