Consider a car moving on  a straight road witha a speed of 100 m/s. Find the distance at which car can be stopped. [mu = 0.5, g = 10 m divided by s squared]

Asked by a.behera67 | 4th Jan, 2016, 09:01: PM

Expert Answer:

begin mathsize 12px style Given colon Speed space of space straight a space car comma space straight u equals 100 space straight m divided by straight s straight mu equals 0.5 straight g equals 10 space straight m divided by straight s squared space Distance space at space which space car space stopped comma space straight s equals ? When space car space stopped space by space friction space then space its space retarding space force space is ma equals μR rightwards double arrow ma equals μmg rightwards double arrow straight a equals μg Consider space straight a space car space covers space straight s space distance space with space velocity space u space and space stops. Using space kinematic space rquation space of space motion straight v squared equals straight u squared minus 2 as space space space left parenthesis since space car space is space retarding comma space straight a space is space negative right parenthesis 0 equals straight u squared minus 2 as 2 as equals straight u squared straight s equals fraction numerator straight u squared over denominator 2 straight a end fraction equals fraction numerator straight u squared over denominator 2 μg end fraction straight s equals fraction numerator 100 squared over denominator 2 cross times 0.5 cross times 10 end fraction rightwards double arrow straight s equals 1000 space straight m  end style

Answered by Priyanka Kumbhar | 5th Jan, 2016, 10:00: AM