HARDIK
Last Activity: 6 Years ago
STRATEGY: SINCE IT IS HITTING THE BUILDING SO TIME TO COVER HORIZONTAL DISTANCE SHOULD BE EQUAL TO TIME TO COVER VERTICAL DISTANCE.
SOLUTION: LET TIME TO COVER HORIZONTAL DISTANCE BE “T”
LET INITIAL VELOCITY BE “U”
NOW, U.COS45.T=30M
>T=30/UCOS45 .....(1)
NOW FOR VERTICAL,
H=UT-1/2(GT^2)
26.4=USIN45(30/UCOS45)-1/2(10(30/UCOS45)^2)
ON SOLVING THE ABOVE EQUATING YOU WILL GET
U=50M/S
ALL THE BEST
REGARDS:HARDIK BAWEJA