Serving at a speed of 170 km/h, a tennis player hits the ball at a height of 2.5 m and an angle θ below the horizontal. the baseline from which the ball is served is 11.9 m from the net, which is 0.91 m high. what is the angle θ such that the ball just crosses the net? will the ball land in the service box, which has an outermost service line is 6.40 m from the net?

serving speed = 170 km/h

now we will convert it into m/s

now it will have two components along x and y directions

also in x and y directions we know

by solving above equation we have

so angle is 6.11 degree below the horizontal

now we have

now time taken by ball to reach the ground will be

now the displacement in x direction will be

now the distance from net will be

So it will land inside the line

see earlier answer

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