Answer:
a. v(1.8) = -3.14 m/s
b. [tex]v_{max} = 3.925\ m/s[/tex]
c. [tex]a_{max} = 3.08\ m/s^2[/tex]
Explanation:
a.
The speed of a particle executing simple harmonic motion is given by the following equation:
[tex]v(t) = -A \omega \ Sin(\omega t)[/tex]
where,
v = velocity = ?
A = Amplitude = 5 m
ω = angular frequency = [tex]\frac{2\pi}{Time Period} = \frac{2\pi}{8\ s}[/tex] = 0.785 s
t = time
First we find time at 3 m by using equation for displacement:
[tex]x = 3\ m = ACos(\omega t)\\Cos((0.785 rad/s)(t)) = \frac{3\ m}{5\ m}\\t(0.785\ rad/s) = Cos^{-1} (0.6)\\t = \frac{0.927\ rad}{0.785\ rad/s}\\t = 1.18 s[/tex]
Therefore,
[tex]v(1.8) = velocity at 3\ m = -A\omega Sin(\omega t)\\v(1.8) = -(5\ m)(0.785\ rad/s)Sin((0.785\ rad/s)(1.18\ s))\\[/tex]
v(1.8) = -3.14 m/s
c.
The maximum speed is given as:
[tex]v_{max} = A\omega\\v_{max} = (5\ m)(0.785\ rad/s)\\[/tex]
[tex]v_{max} = 3.925\ m/s[/tex]
The maximum acceleration is given as:
[tex]a_{max} = A\omega^2\\v_{max} = (5\ m)(0.785\ rad/s)^2\\[/tex]
[tex]a_{max} = 3.08\ m/s^2[/tex]