Question

question 15 (1 point)
a brick is dropped from the top of a building. a second brick is thrown straight down from the same building. they are released at the same time. neglect air resistance. compare the accelerations of the two bricks.
the first brick accelerates faster.
the second brick accelerates faster.
the two bricks accelerate at the same rate.
it is impossible to determine from the information given.
page 15 of 20

Explanation:

When air resistance is neglected, the only force acting on both bricks is gravity. According to Newton's second law \(F = ma\), and the force due to gravity \(F = mg\). So, \(mg=ma\), which simplifies to \(a = g\) (where \(g\) is the acceleration due to gravity approximately \(9.8\ m/s^{2}\) near the Earth's surface). The initial velocity (whether it is zero for the dropped brick or non - zero for the thrown brick) does not affect the acceleration. Acceleration is determined by the net force and mass (\(a=\frac{F_{net}}{m}\)), and here \(F_{net}=mg\) for both bricks.

Answer:

The two bricks accelerate at the same rate.