In: Physics
a)
at time 't' the distance in horizontal direction between the car and balloon=0
the distance traveelled by the car=Vot
so,
d-Vot=0
d=Vot
t=d/Vo ----(1)
time taken for the balloon to come down=t=sqrt(2h/g) --(2)
from (1) and (2)
d/V0=sqrt(2h/g)
Vo=d/sqrt(2h/g)
speed of the car,Vo= d/sqrt(2h/g)
b)
distance travelled by the car=(Vo*tb)+(Vo^2/as)-1/2*(as)*(Vo/as)^2
d-((Vo*tb)+(Vo^2/as)-1/2*(as)*(Vo/as)^2)=0
d-Vo*tb-Vo^2/as=0
(d-Vo^2/as)/Vo=tb
Vo-t*as=0 ===> t=Vo/as--(1)
t= time for which the car moves after the brakes are applied
time taken by the ballon to reach=sqrt(2h/g)
total time taken by the car=t+tb
t+tb=sqrt(2h/g)
from (1) )
Vo/as +tb =sqrt(2h/g)
Vo=as*(sqrt(2h/g) -tb)
c)substituting the value of tb in the above equation we get
Vo=as(sqrt(2h/g)-(d-Vo^2/as)/Vo)
=as(sqrt(2h/g)) -(d*as-Vo^2)/Vo
and solving for Vo
we get
Vo =d/sqrt(2h/g) -some thing
so Vo in part(2) is less than Vo in part(1)