A body of 3 kg moves in the XY plane under the action of

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A body of 3 kg moves in the XY plane under the action of a force given by 6t î + 4t ĵ . Assuming that the body is at rest at time t = 0, the velocity of the body at t = 3s is

1. 6î - 6ĵ
2. 18î + 6ĵ
3. 18î + 12ĵ
4. 12î + 18ĵ

Correct Option: C

F^{^→} = 6t î + 4t ĵ
F_x = 6t , F_y = 4t

a_x =	6t	= 2t , a_y =	4t
	3		3

v_x = 0 + 2t . t = 18 , for t = 3s

v_y = 0 +	4	t.t = 12 for t = 3s
	3

Velocity → 18î + 12ĵ