a particle is moving in x-y-plane at `2 m//s` along x-axis. `2` seconds later, its velocity is `4 m//s` in a direction making `60^(@)` with positive x-axis. Its average acceleration for the period of motion is:-A. `sqrt(5) m//s^(2)`, along y-axisB. `sqrt(3) m//s^(2)`, along y-axisC. `sqrt(5) m//s^(2)`, along at `60^(@)` with positive x-axisD. `3m//s^(2)` at `60^(@)` with positive x-axis.

a particle is moving in x-y-plane at `2 m//s` along x-axis. `2` second

1.	a particle is moving in x-y-plane at `2 m//s` along x-axis. `2` seconds later, its velocity is `4 m//s` in a direction making `60^(@)` with positive x-axis. Its average acceleration for the period of motion is:-A. `sqrt(5) m//s^(2)`, along y-axisB. `sqrt(3) m//s^(2)`, along y-axisC. `sqrt(5) m//s^(2)`, along at `60^(@)` with positive x-axisD. `3m//s^(2)` at `60^(@)` with positive x-axis.
Answer» Correct Answer - B `v_(i)=2hat(i)` `v_(f)=4 cos 60^(@) hat(i)+4 sin 60^(@) hat(j)` `=4/2hat(i)+(4sqrt(3))/2hat(i)` `=2hat(i)+2sqrt(3) hat(j)` `Deltavec(v)=vec(v)_(f)-vec(v)_(i)=2hat(i)+2sqrt(3)hat(j)-2hat(i)=2sqrt(3) hat(j)` `lt lt vec(a)gt gt =(2sqrt(3)hat(j))/2=sqrt(3)hat(j) m//s^(2)`

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