A motorcyclist is traveling along a road and accelerates for 4.50s to pass another cyclist. The angular acceleration of each wheelis +6.70 rad/s^2, and, just after passing, the angular velocity ofeach is +74.5 rad/s, where the plus signs indicate counterclockwisedirections. What is the angular displacement of each wheel duringthis time?
a. +221 rad
b. +131 rad
c. +335 rad
d. +355 rad
e. +267 rad

Respuesta :

Answer:

Angular displacement of the wheel, [tex]\theta=267.41\ rad[/tex]

Explanation:

It is given that,

Angular acceleration of the wheel, [tex]\alpha =6.7\ rad/s^2[/tex]

Final speed of the wheel, [tex]\omega_f=74.5\ rad/s[/tex]

Time taken, t = 4.5 s

Initially, it is required to find the initial angular velocity of the wheel. Using the first equation of rotational kinematics as :

[tex]\omega_f=\omega_o+\alpha t[/tex]

[tex]\omega_o[/tex] is the initial speed of the wheel

[tex]\omega_o=\omega_f-\alpha t[/tex]

[tex]\omega_o=74.5-6.7\times 4.5[/tex]

[tex]\omega_o=44.35\ rad/s[/tex]

Let [tex]\theta[/tex] is the angular displacement of each wheel during this time. Using the second equation of motion as :

[tex]\theta=\omega_o t+\dfrac{1}{2}\alpha t^2[/tex]

[tex]\theta=44.35\times 4.5+\dfrac{1}{2}\times 6.7\times (4.5)^2[/tex]

[tex]\theta=267.41\ rad[/tex]

So, the angular displacement of each wheel during this time is 267 radian.