An athlete completes one round of a circular track of radius $$R$$ in $$40\,\sec .$$ What will be his displacement at the end of $$3\,\min. \,20\sec .$$ ?
A.
Zero
B.
$$2R$$
C.
$$2\,\pi R$$
D.
$$7\,\pi R$$
Answer :
Zero
Solution :
Total time of motion is $$3\,\min \,20\sec = 20\,\sec .$$ As time period of circular motion is $$40\,\sec $$ so in $$20\,\sec $$ athlete will complete 5 revolution i.e., he will be at starting point i.e., displacement = zero.
Releted MCQ Question on Basic Physics >> Kinematics
Releted Question 1
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