PHSX 211 10th Edition Lecture 14 Outline of Last Lecture Practice ProblemsI. Make a list of how you would solve a force problem in general.II. If we include the drag force in projectile motion, what mathematical complications does in introduce?III. At which three points on the rotating disk is velocity and angular velocity greatest?Outline of Current Lecture Practice ProblemsI. Draw a free body diagram of Tarzan swinging from a vine right after he steps off a branchand when we is at the lowest point in his swing.II. If you are twirling a ball on a swing vertically, what is the minimum speed at the top of the circle to keep the ball going? (Using variables)III. If you are driving a car with your crush sitting to your right, which way should you turn so they slide into you? If the static friction coefficient is .4 and the velocity is 18 m/s, what is the maximum radius you can make while turning?Current LecturePractice ProblemsIV. Draw a free body diagram of Tarzan swinging from a vine right after he steps off a branchand when we is at the lowest point in his swing.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute. TensionTangential AccelerationmgmgRadial AccelerationVelocity of TarzanV. If you are twirling a ball on a swing vertically, what is the minimum speed at the top of the circle to keep the ball going? (Using variables)a. The tension at the top of the circle at the minimum speed would be zero.b. Since the ball is moving in a uniform circular motion, it has to tangential acceleration.c. Its radial force then would equal the velocity squared, multiplied by the mass, divided by the radius, and would also equal the weight minus the tension, which in this case would be zero:mv2r= mg −Td. In this case, T = 0, so the equation simples to: V =√rgVI. If you are driving a car with your crush sitting to your right, which way should you turn so they slide into you? If the static friction coefficient is .4 and the velocity is 18 m/s, what is the maximum radius you can make while turning?a. You should turn to the right to force your crush sitting next to you to slide righti. This is because your crush’s tangential velocity wants to keep going the same the direction, but because the car is accelerating around a circle, the car “runs into your crush”.b. Because the car is going at a constant velocity there is no tangential acceleration.The radial acceleration would equal the friction force at maximum radius.ar=v2rmv2r=Friction Forcemv2r=ᶣsmgr=v2ᶣsgr=(18)(18)(.4 )(9.8)=¿82.7
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