MasteringPhysics: Relative and Circular Motion - Microsoft Edge https://session.
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MasteringPhysics: Relative and Circular Motion - Microsoft Edge https://session.masteringphysics.com/myct/itemView?assignmentProblemID-930 Relative and Circular Motion Conceptual Question 4.12 PartA In uniform circular motion, which of the following quantities are constant? Check all that apply the tangential component of velocity speed the radial component of acceleration instantaneous velocity the tangential component of acceleration Submit Previous Answers Request Answer XIncorrect Try Again; 2 attempts remaining Part B Which of these quantitionExplanation / Answer
See, velocity and acceleration are vector quantities. So even if their magnitude is constant, we have to take care of direction as well. In uniform circular motion speed is constant (speed is scalar, velocity is vector).
Tangential component of velocity will keep on changing its direction although its magnitude is constant in uniform circular motion. Hence, it is not constant.
The radial component of accn always act towards the center of circle. Hence it will be constant.
Similarly instantaneous velocity and tangential acceleration will not be constant because they will change their direction regularly.
Hence, option b and c are correct.