Hey guys..............cud ull pls help me wit these sums on projectiles?
1) The equation of the path of a projectile is y=0.5x-0.02x^2. Determine the initial speed of the projectile?
2) A tennis player strikes the ball at a height of 0.5m. It passes above her opponent 10m away at a height of 4m, and lands 20m from the first player, who has not moved since striking the ball. Calculate the angle of projection of the ball??
1) let theta=a
y=xtana-(gx^2/2u^2 (cosa)^2))
tana=0.5 and 0.02=10/(2u^2 (cosa)^2))
from the first equation a=26.6
and substituting a in the second equation we get u= 17.7 m/s
2) substitute all the variables each time in pairs of three in the equation of a trajectory as follows-->
again theta=a
0.5=-(10x^2/2u^2 (cosa)^2))
0=20tana-(10(20^2)/2u^2 (cosa)^2))
4=10tana-(10(10^2)/2u^2 (cosa)^2))
solve them ull get ur ans