Problem

Two children are having a snowball fight, and one is trying to land a snowball on a frie...

Two children are having a snowball fight, and one is trying to land a snowball on a friend who is hiding behind a wall (Fig. Q4.2). The child on the left can only throw snowballs with one value of the initial speed and finds that for one throwing angle a that is less than 45° he is able to have his snowball land on his friend. Show that there is a corresponding throwing angle b greater than 45° that yields the same value of the range and find a general relation between Hint: Consider the range of a projectile as calculated in Equation 4.28 (i.e., ignoring the effect of air drag), and assume that the snowballs in Figure Q4.2 start and land at the same height above the ground.