1/2+-2/5t(+2/5)=1/5t+t(+2/5)
simplify
1/2=2 and 3/5t
change to a decimal
.5 = 2.6t
divide both sides by 2.6
.5/2.6 2.6t/2.6
you get T= .3125
Hello,
y=-g/2 t²+25 t is the trajectoire with g=9.81 m/s²
y=-g/2 (t²-25*2/g t)
==>y=-g/2(t²-2*25/g t +25²/g²)+25²/g² * g/2
==>y=-g/2(t-25/g)²+25²/(2g)
==> h=25²/(2g)=625/(2*9.81*3.28084)=9,709479... feet
(for 1m=3.28084 feet)
54+9= 63 m = distance and time=35 sec hence, speed= 63/35=9/5=1.8 m/s
time taken to reach water surface= distance/speed=54/1.8=30 sec