in this video we're going to look at what kinetic energy is and show you how to calculate it using the equation now the kinetic energy of an object is the energy that it possesses due to its motion so anything that's moving has kinetic energy whether it's a plane or a particle how much energy an object has though depends on two things its speed and its mass for speed the faster an object is moving the more kinetic energy it will have which kind of makes sense because if you think about any fast moving object it must have had lots of energy transferred to it in order to speed it up and that energy is stored in the kinetic energy store so fast objects have lots of kinetic energy meanwhile for mass as long as everything else is kept equal for example the objects have the same speed then the more mass an object has the more kinetic energy you'll have so if our particle weighed 0.1 grams but our plane weighed 20 tons and both of them were traveling at 900 meters per second the plane would have much more kinetic energy because it has a much larger mass but the speeds are the same what if instead though the plane was traveling at five meters per second and the particle was traveling at 4 000 meters per second in order to find out which object had the most kinetic energy this time we'd have to use the equation which states that e k equals one half m v squared if you're not familiar with this equation the e stands for energy and the little k means it's kinetic energy then m is mass which we measure in kilos and v is velocity which for the sake of this question is the same as speed and is measured in meters per second so as with any question once we have our equation the next step is to make sure all of our values are in the correct units so we have to change twenty tons to twenty thousand kilos as our one thousand kilos in each tonne and we need to divide zero point one grams by one thousand to get 0.0001 kilos and we're now ready to plug these values into our equations for the plane we do one-half or 0.5 times its mass of 20 000 kilos times its speed of 5 squared and remember that it's only the speed that's being squared not the entire thing so that gives us 250 000 which will be in joules because we measure energy in joules and we could rewrite it as 250 kilojoules as the k just means 1000 meanwhile for the particle we do 0.5 times 0.0001 times 4000 squared which gives us 800 joules or 0.8 kilojoules so even though the particle was traveling much faster it still had less kinetic energy because its mass was so much lower anyway that's all for this video so hope you enjoyed it and we'll see you next time