Question

a particle moves over three quarters of a circle of radius r .what is magnitude of displacement

Answer 1

Given particle covers three quarters of a circle with radius R.Distance travelled = 3/4(circumference of circle) =3/4(2*pi* r) = 3/2 ( pi* r). DISPLACEMENT=SHORTEST PATH = IF WE JOIN POINT A and B we get right angle triangle withHypotenuse(displacement) and other two sides of triangle with sides r. Displacement =Sqr(r^2 +r^2)=sqr(2r^2)=r*sqr(2)=1.41*r metersTherefore
Displacement covered by particle is 1.414*r m

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