Question

the ball is 150g heavy and it is dropped from 300m, what is the velocity of the ball just before it touches the ground

Answer 1

Answer:

77.5 m/s

Step-by-step explanation:

Once the ball is dropped from the height, it converts all its potential energy into kinetic energy:

$P. E = K.E\\mgh = \frac{1}{2}mv^2$

Using this equation, and the data we have to find the velocity of the ball:

$mass = 150 \ g \\gravity = 10 \ m/s^2\\height = 300 m$

$P.E = mgh\\150 \times 10 \times 300 = \frac{1}{2} \times 150 \times v^2\\\\150 \times 10 \times 300 = 75 \times v^2\\\\v^ 2 = \frac{150 \times 10 \times 300 }{75}\\\\v^2 = 6000\\\\v = \sqrt {6000}\\\\v = 77. 5 \ ms^{-1}$