ap physics c problems

Test Preparation AP Sciences
1

<p>can someone help me with these 2 problems</p>

<p>A hot air balloon is going upward at a constant speed of 5.7 m/s. When
it is 34 m above the ground, a package is
released from the balloon.
After it is released, for how long is the
package in the air? The acceleration of gravity
is 9.8 m/s2 . </p>

<p>and</p>

<p>A golf ball is released from rest from the top
of a very tall building. Choose a coordinate
system whose origin is at the starting point
of the ball, and whose y axis points vertically
upward.
Neglecting air resistance, calculate the ve-
locity of the ball after 5.6 s. The acceleration
of gravity is 9.8 m/s2 .</p>

2

<p>1) Break apart the problem into two parts: The package will keep moving upwards (vo = 5.7) for a short time (find time; a = g = -9.8) until it reaches its maximum height (vf = 0); Then the package will be a free-fall problem (find time) where vo = 0.</p>

<p>The time can be found by rearranging a kinematics formula using algebra.</p>

<p>2) vo = 0; t = 5.6; a = -9.8
Plug and chug: vf = vo + at</p>

<p>(vf = final velocity; vo = initial velocity; a = acceleration; t = time; g = gravity)</p>