Level:
Project ID:
9000117701
Accepted:
1
Clonable:
0
Easy:
0
A body is thrown at the initial angle \(\alpha = 30^{\circ }\)
and the initial velocity \(v_{0} = 20\, \mathrm{m}/\mathrm{s}\).
The trajectory of the body is a part of parabola. Find the directrix of this
parabola. Hint: The coordinates of the moving body as functions of time are
\[
\begin{aligned}x& = v_{0}t\cdot \cos \alpha , &
\\y& = v_{0}t\cdot \sin \alpha -\frac{1}
{2}gt^{2}.
\\ \end{aligned}
\]
Consider the standard acceleration due to gravity
\(g = 10\, \mathrm{m}/\mathrm{s}^{2}\).
\(y = 20\)
\(y = 5\)
\(y = 15\)
\(y = 10\)