# Projectile of ball launched to a specific height#

A ball is launched vertically at Point A with an initial speed of $$v = {{params.v0}} m/s$$. It passes through the Point C twice, once on the way up ($$t_1$$), and again on the way down ($$t_2$$). Ignoring air resistance and drag, answer the following questions relative to an observer standing 405 $$m$$ away, at Point B.

## Part 1#

At what time $$t_1$$ will the line of sight make a $$\theta$$ = 45 $$^{\circ}$$ angle with the horizontal?

Hint: The line of sight is the dotted line connecting Point B to Point C.

Please enter in a numeric value in $$seconds$$.

## Part 2#

Compute the velocity of the ball at $$t_1$$ (Positive if up, negative if down).

Please enter in a numeric value in $$m/s$$.

## Part 3#

At what time $$t_2 s$$ will the line of sight make a $$\theta$$ = 45 $$^{\circ}$$ angle with the horizontal?

Hint: The line of sight is the dotted line connecting Point B to Point C.

• Please enter in a numeric value in $$seconds$$.

## Part 4#

Compute the velocity of the ball at $$t_2$$ (Positive if up, negative if down).

Please enter in a numeric value in $$m/s$$.