Question

Assume the acceleration of the object is a(t) = −32 feet per second per second. (Neglect air resistance.) With what initial velocity must an object be thrown upward (from ground level) to reach the top of a national monument (560 feet)? (Round your answer to three decimal places.)

Answer 1

Answer:

$v_i=189.315ft/s$

Explanation:

We are going to use the accelerated motion formula $v_f^2=v_i^2+2ad$ on the vertical component taking the upwards direction as positive.

Since at maximum height the speed will be $v_f=0m/s$, the formula can be written as $v_i=\sqrt{-2ad}$, which for our values is:

$v_i=\sqrt{-2(-32ft/s^2)(560ft)}=189.314553059ft/s=189.315ft/s$

Written to three decimal places.