Here is a picture of the problem: (my symbols are not appearing on chegg) style=

Question

Here is a picture of the problem: (my symbols are not appearing on chegg)style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

http://i1334.photobucket.com/albums/w655/salonemark/ProblemDynamics_zpsdf82ba80.jpg>

style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

Here is a enlarged picture of the turntable diagramstyle="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

http://i1334.photobucket.com/albums/w655/salonemark/TurntableProblem_zpsa0222e4d.jpghref="http: i1334="" photobucket="" com="" albums="" w655="" salonemark="" turntableproblem_zpsa0222e4d="" jpg="">

href="http: i1334="" photobucket="" com="" albums="" w655="" salonemark="" turntableproblem_zpsa0222e4d="" jpg="">

A mass is resting on a horizontal turntable. The coefficients of friction between the mass and the turntable are %u03BCs=%u03BCk=0.5, and L==1 m. At t=0 the initially stationary turntable is accelerated at the constant rate of  style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">%u04EA= 4 rad/s^2. At what time will the mass begin to move?style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

>style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">style="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">%u04EA= 4 rad/s^2. -------> this is theta double dot equalsstyle="color: rgb(51, 51, 51); font-family: arial, helvetica, clean, sans-serif; font-size: 13px; line-height: 16px;">

A mass is resting on a horizontal turntable. The coefficients of friction between the mass and the turntable are %u03BCs=%u03BCk=0.5, and L==1 m. At t=0 the initially stationary turntable is accelerated at the constant rate of %u04EA= 4 rad/s^2. At what time will the mass begin to move?

Explanation / Answer

Force due to pseudo acceleration acting on the mass m is ma.

Where a is tangential acceleration = r*alpha.

Here, alpha = 2 rad/s^2, so a = 1m * 2 rad/s^2 = 2 m/s^2

We have radial acceleration is A = v^2/L = v^2, where v = LW^2 = W^2

We know alpha = 4, so W = 4t +c. But at t=0, we have W=0, so c=0.

So W = 4t.

For object to start moving, maximum static friction = pseudoforce + radial force

=> umg = ma + m*(W)^2 => 2 + 16t^2 = 0.5(9.8)

=> t^2 = (2.9)/16

=> t = 0.42573 seconds.

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.