A football of mass m = 1 kg is thrown at an initial velocity of v0 = 9 m/s at an angle of θ = 34° with respect to the horizontal. The ball reaches a maximum height of h. Let gravitational potential energy be zero at ground level. Give an expression for the initial velocity vector in rectangular form. Write your answer in terms of v0, θ, and the unit vectors i and j.

Distance covered = speed x timethe distance traveled going against the stream = distance traveled with the stream.therefore it is the speed and the time that are the variables.as he travels the same distance both ways, speed x time is the same for each way.going upstream his speed is 4 kph; going downstream his speed is 6 kph.therefore we have two simultaneous equations: time upstream x 4 = time downstream x 6time upstream + time downstream = 60 minutestherefore we have the equation: time upstream = 6/10 hour, time downstream therefore = 4/10 hour.distance traveled at 4km/hr in 6/10 hour = 24/10 = 2.4km.check: distance traveled at 6km/hr in 4/10 hour = 24/10 = 2.4km.