Question #0c86a

1 Answer
Jun 21, 2016

Discussed below

Explanation:

Given

hThe height from which the canon ball was fired=60m

uThe vlocity of projection=25ms

αAngle of projection=53

And sin53=0.8andcos53=0.6

Now

Horizontal component of vel.of projection ucos53=250.6=15ms

Vertical component of vel.of projection usin53=250.8=20ms

At the time when it reaches at maximum height H from its point of projection its vertical component becomes zero, So considering g=ms2 we get

02=202210HH=20m

Hence at its maximum height the total height fron ground
Htotal=60+20=80m

Now if its time of flight be t s
then it will undergo a vertical displacement downward during this time. So
-
60=20t1220t2

t22t6=0

t=2+44(6)12

t=(7+1)s

Net horizontal displacement during this time of flight

=ucosαt=15(7+1)m