What is Momentum ?

Hi friends what do you think is more dangerous  a coconut falling from a tree or a bullet fired   from a gun let's find out in this video I'm sure  you're thinking a bullet is more dangerous right   we think a bullet is more dangerous since it  travels really fast now speed of the bullet   depends on the type of gun used let's take  the average speed of the bullet as 400 meters   per second now that's really fast because it  means it's traveling 400 meters every second   now what is the speed of the coconut  when it falls from a coconut tree   in case you guys missed my video on how  dangerous is a falling coconut do check it out   as we saw in the video the height of  the coconut tree was about 15 meters   if the coconut falls from the top of the tree how  do we calculate the speed when it hits the ground   we can use the equations of motion to find  out because when the coconut starts to fall   what will be its initial velocity that's  right zero since the motion has just started   and the distance or displacement traveled by  the coconut is 15 meters the height of the tree   the coconut is falling faster and faster it's  accelerating due to gravity so we need to use   the acceleration due to gravity G which is  approximately 10 meters per second squared   now with this data we can use the third  equation of motion V Square equal to U   squared plus 2as to calculate the final  velocity when the coconut hits the ground   so if you substitute the values and do the  calculations you'll get that the final velocity   V is square root of 300 which is 17.32 meters  per second or approximately 17 meters per second   of course we are ignoring the air friction here  so if we compare the speed of the bullet and the   speed of the falling coconut clearly the bullet  is much faster but don't you think we also need   to consider how heavy the moving object is so  we also need to consider the mass of the object   and that's why it's better to use the concept  of momentum in physics and not just velocity   what is momentum momentum is the product of mass  and velocity so it considers both these quantities   and it can help us to determine how  dangerous the moving object is going to be   now what is the mass of the bullet it depends  on the type of bullet let's take the average   mass of the bullet as 10 grams so the momentum  of the bullet will be mass times velocity which   is 10 grams multiplied by 400 meters per second 10  grams is 10 by 1000 kg remember we need to convert   to SI units so which is 1 by 100 kg and when we  multiplied with the velocity the momentum of the   bullet is 4 kg meter per second now let's look at  our coconut the mass of the coconut is about 1 kg   and if you multiply it with the velocity with  which the coconut hits the ground the momentum   is about 17 kg meter per second so as you can  see the Coconuts momentum is about four times   the momentum of the moving bullet so the coconut  will be more dangerous if it hits the person   because when it hits the person it will  transfer this large momentum to the person   the force will be high and it can  really hurt or even kill the person   the bullet has a much lower momentum  but since it's pointed and sharp it can   go into the person's body and can cause  internal damage which can also be deadly   so as you learned that based on physics a falling  coconut is actually more dangerous than a fast   moving bullet because it has large mass and hence  its momentum is much higher than a moving bullet   now if we consider a car which is moving very  slowly at a speed of only one meter per second   and it collides against a wall or a person do  you think it's dangerous let's say the mass of   the car is about 1000 kg so see if you can apply  the concept of momentum and decide if this slow   moving car is also dangerous the mass of the car  is 1000 kg and its speed is 1 meter per second   and do let me know what do you think by putting  it in the comments below and if you like this   video do hit the like button and share it out with  your friends and if you haven't subscribed to our   YouTube channel what are you waiting for please  hit the Subscribe button right now and click on   the notification Bell so that you don't miss any  of our interesting science and maths videos and   study tips videos and do check out the full  courses on our website manochaacademy.com and   our Android App Manocha Academy we have courses  on physics chemistry biology maths and computer   coding in these courses you're gonna get live  classes interactive videos quizzes questions   mock tests and revision notes so do check  out our courses I'll put the links below and   please do share it with your friends and do stay  connected with Manocha Academy and keep learning

Channel: Manocha Academy

Views: 118,802

Keywords: what is momentum, momentum, momentum physics, momentum class 9, momentum class 11, what is momentum class 9, what is momentum class 11, what is momentum in physics, what is momentum class 9th, velocity, mass, physics, science, manocha academy, manocha academy physics, manocha, sandeep manocha

Id: IrcN3yxzuhI

Length: 5min 58sec (358 seconds)

Published: Sun Oct 16 2022