Question

A basketball rolls off a deck that is 3.2 m from the pavement. The basketball lands 0.75 m from the edge of the deck. How fast was the basketball rolling? Seema lists the given values in a chart and determines that the unknown value is vx. Which describes Seema’s error? a) The y and x values are switched. b) The unknown is , not vx. c) The value for ay is not known. d) The value of y should be –3.2 m.

Answer 1

Answer:

d). The value of y should be -32m

Vx=0.92 m/s

Explanation:

Using equation of motion uniform to y motion

$x_{f}=x_{o}+v_{o}*t+\frac{1}{2}*a*t^{2}\\x_{o}=0m\\v_{o}=0\\x_{f}=\frac{1}{2}*a*t^{2}\\x_{f}=-3.2m \\a=g=-9.8\frac{m}{s^{2}}$

So to find t that is the same time for all the motion

$t^{2}=\frac{2*x_{f}}{a} \\t=\sqrt{\frac{2*x_{f}}{a}}=\sqrt{\frac{2*-3.2m}{-9.8\frac{m}{s^{2}}}}\\t=0.808s$

The value of Xf=-3.2m because the g is negative from the axis

Now in the axis 'x' to find Vx

$Vx=\frac{0.75m}{0.808S}\\ Vx=0.92 \frac{m}{s}$