What did I do wrong in these PCS211 questions? Please take your time to correct it carefully!

3. [1/2 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.2.P.003. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A wheel starts from rest and rotates with constant angular acceleration to reach an angular speed of 11.0 rad/s in 2.98 s. (a) Find the magnitude of the angular acceleration of the wheel. 3.7 rad/s2 (b) Find the angle in radians through which it rotates in this time interval. 32.78 1x This would be the angle if the wheel rotated at a constant angular speed of 11.0 rad/s over the time interval. rad Need Help? Read it Watch It4. [0/2 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.2.OP.004.MI. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER An electric motor rotating a workshop grinding wheel at 1.14 x 10 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 1.98 rad/s. (a) How long does it take the grinding wheel to stop? 0.95 X The angular speed is given in rev/minute. You appear to have used an initial angular speed of 114 rev/s. s (b) Through how many radians has the wheel turned during the time interval found in part (a)? 1.805 X It might be helpful to translate this problem into linear variables (a car traveling with an initial speed and then slowing down with a constant negative acceleration). rad Need Help? Read It Master It 5. [0/1 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.2.OP.005. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A rotating wheel requires 2.92-s to rotate through 37.0 revolutions. Its angular speed at the end of the 2.92-s interval is 98.4 rad/s. What is the constant angular acceleration of the wheel? 8.67 X Note that we do not know the initial angular speed (it is not zero). You will need to eliminate the initial angular speed from a constant acceleration equation. rad/s Need Help? Read It Watch It7. [2/5 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.3.OP.010.MI. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A wheel 2.30 m in diameter lies in a vertical plane and rotates about its central axis with a constant angular acceleration of 4.10 rad/s. The wheel starts at rest at t = 0, and the radius vector of a certain point P on the rim makes an angle of 57.30 with the horizontal at this time. At t = 2.00 s, find the following. (a) the angular speed of the wheel 8.2 rad/s (b) the tangential speed of the point P 9.43 m/s (c) the total acceleration of the point P magnitude 8.26 X Your response differs from the correct answer by more than 10%. Double check your calculations. m/s direction 61.38 X Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. . with respect to the radius to point P (d) the angular position of the point P 1 X Your response differs from the correct answer by more than 10%. Double check your calculations. rad8. [3/5 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.3.OP.011.MI. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A disk 8.04 cm in radius rotates at a constant rate of 1 160 rev/min about its central axis. (a) Determine its angular speed. 121.41 rad/s (b) Determine the tangential speed at a point 3.06 cm from its center. 3.71 m/s (c) Determine the radial acceleration of a point on the rim. magnitude 1185.127 1x Note that the expected units are km/s2. km/s2 direction toward the center v v (d) Determine the total distance a point on the rim moves in 1.94 s. 7.19 X You appear to have correctly calculated this distance using your incorrect value from part (b). m Need Help? Read It Master It 9. [0/1 Points] DETAILS PREVIOUS ANSWERS SERPSET9 10.P.024. MY NOTES ASK YOUR TEACHER A car traveling on a flat (unbanked), circular track accelerates uniformly from rest with a tangential acceleration of a. The car makes it one quarter of the way around the circle before it skids off the track. From these data, determine the coefficient of static friction between the car and the track. (Use any variable or symbol stated above along with the following as necessary: g for the acceleration of gravity.) HS X Submit Answer10. [1/4 Points] DETAILS PREVIOUS ANSWERS SERPSE10 10.3.P.013. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER In a manufacturing process, a large, cylindrical roller is used to flatten material fed beneath it. The diameter of the roller is 8.00 m, and, while being driven into rotation around a fixed axis, its angular position is expressed as 0 = 2.60t2 - 0.200ts where 0 is in radians and t is in seconds. (a) Find the maximum angular speed of the roller. 1.548 X Your response differs from the correct answer by more than 10%. Double check your calculations. rad/s (b) What is the maximum tangential speed of a point on the rim of the roller? 6.16 X Your response differs from the correct answer by more than 10%. Double check your calculations. m/s (c) At what time t should the driving force be removed from the roller so that the roller does not reverse its direction of rotation? 8.6 v s (d) Through how many rotations has the roller turned between t = 0 and the time found in part (c)? 16.69 X Your response differs from the correct answer by more than 10%. Double check your calculations. rotations