Use the worked example above to help you solve this problem. A ball is thrown upward from the top of a

building at an angle of $30\mathrm{.}0$ to the horizontal and with an initial speed of $18\mathrm{.}0\frac{m}{s}.$ The point of release is

$h=48\mathrm{.}0m$ above the ground.

$($a$)$ How long does it take for the ball to hit the ground?

$s$

$($b$)$ Find the ball's speed at impact.

$\frac{m}{s}$

$($c$)$ Find the horizontal range of the ball.

m

EXERCISE

HINTS: GETTING STARTED I I$\text{'}$M STUCK!

Suppose the ball is thrown from the same height as in the PRACTICE IT problem at an angle of $38\mathrm{.}0$

below the horizontal. If it strikes the ground $42\mathrm{.}0m$ away, find the following. $($Hint: For part $($a$),$ use the

equation for the $x-$displacement to eliminate $v_{0}t$ from the equation for the $y-$displacement.$)$

$($a$)$ the time of flight

$s$

$($b$)$ the initial speed

$\frac{m}{s}$

$($c$)$ the speed and angle of the velocity vector with respect to the horizontal at impact

speed

$\frac{m}{s}$

angle

below the horizontal