A rigid link PQ is 2 m long and oriented at 20° to the

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A rigid link PQ is 2 m long and oriented at 20° to the horizontal as shown in the figure. The magnitude and direction of velocity V_Q, and the direction of velocity V_P are given. The magnitude of V_P (in m/s) at this instant is

1. 2.14
2. 1.89
3. 1.21
4. 0.96

Correct Option: D

By Instantaneous center method;say ω = angular velocity of rod
v_q = r_q . ω ...(i)
v_p = r_p . ω ...(ii) Dividing equation (i) with equation (ii) we get

	v_q	=	r_q	; v_p =	r_p	.v_q
	v_p		r_p		r_q

Now by sine law,	r_p	=	r_q
	sin(45° + 20°)		sin(70°)

	r_p	=	sin(65°)
	r_q		sin(70°)

So , v_p =	sin(65°)	v_q = 0.96
	sin(70°)