Question

A baseball is thrown horizontally from a cliff at 30 m/s and lands 7 seconds after the baseball was thrown. Calculate the horizontal AND vertical distance.

Answer 1

Answer:

The horizontal and vertical distances are x = 210 m and y = -240.35 m, respectively.

Explanation:

Using the equation of the displacement in the x-direction, we have:

(let's recall we have a constant velocity in this direction)

$x=v_{ix}t$

Where:

• v(ix) is the initil velocity in the x direction (v(ix) = 30 m/s)
• t is the time (t = 7 s)

$x=30(7)$    

$x=210\: m$    

Now, we need to use the equation of the displacement in the y-direction to find the vertical distance. Here we have an acceleration (g)

$y=v_{iy}t-\frac{1}{2}gt^2$

Where:

• v(iy) is the initial velocity at the y-direction. In this case, it will be 0
• t is the time
• g is the acceleration of gravity (g=9.81 m/s²)

Then, the vertical position at 7 s is:

$y=-\frac{1}{2}(9.81)(7)^2$

$y=-240.35\: m$

Therefore, the horizontal and vertical distances are x = 210 m and y = -240.35 m, respectively. The minus sign means the negative value in the y-direction.

I hope it helps you!