a ball is dropped from a height h above the ground it loses 50% of its velocity on every impact with the ground before bouncing up what is the total distance travelled by the ball when it finally comes on the ground?
the answer is 1.67h
well this type of questions usually goes in exponential forms a kind of exponential decay because imagine a ball loosing its velocity half of it in every impact..so it will be bouncing till infinite time.. if u say.. so our answer will be in approximation..
well start it from here ball is dropped from height h hence the velocity it will attain before hitting the ground is V & the relation is V^2-0^2=2*10*h hence h=V^2/20 this is the prime relation we will be using in entire solution.. think for the interval 2 when ball goes up after hitting the ground.. our initial velocity is now v/2.. now apply this equation.. to find the distance travelled when it goes up.. 0^2-(V/2)^2=2*10*S1 we have S1=(V^2/20)*1/4 no the total distance travelled when it goes up & down in total is 2S1 so distance travelled in this interval is 2S1=h/2 similarly when u solve for the 2nd interval when ball hits the ground & rebouncd with speed V/4 u will get the distance travelled as h/8.. for next interval..h/32 for next h/128 we have to sum h+(h/2+h/8+h/32+h/128.............) this sum goes to infinity as i told earlier the term in the bracket is a geometric progression having first term as h/2 & common ratio as 1/4 hence the total distance travelled is h+(2h/3)=5h/3 approximately equals to 1.67h
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