Respuesta :
Answer:
Minimum speed required = 12 m/s
Explanation:
Let the speed be y, and upward direction be positive
Consider the vertical motion of car:-
Initial velocity, u = ysin24
Acceleration, a = -9.81 m/s²
We need to find time when displacement is zero, ( s = 0m )
Substituting in s = ut + 0.5at²
0 = ysin24 x t + 0.5 x -9.81 x t²
4.905t² - ysin24 x t = 0
t (4.905t - ysin24 ) = 0
t = 0 or [tex]t=\frac{ysin24}{4.905}=0.083y[/tex]
Here time = 0 is not considered,
So t = 0.083 y
Consider the vertical motion of car:-
Initial velocity, u = ycos24
Acceleration, a = 0 m/s²
Time, t = 0.083y
We need to find speed when displacement is 10.9 m, ( s = 10.9 m )
Substituting in s = ut + 0.5at²
10.9 = ycos24 x 0.083y + 0.5 x 0 x (0.083y)²
0.076y² = 10.9
y = 11.99 = 12 m/s
Minimum speed required = 12 m/s
