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4. A particle starts at the point (8 m, 0 m) with a velocity of (-3 j) m/s. If it experiences a constant acceleration of (-3.5 i + 6 j) m/s2, after how much time does it cross the y-axis?

User Artwl
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1 Answer

6 votes

Answer:

t = 1.51 s

Step-by-step explanation:

Initial position of the particle is given as


r_1 = (8m, 0m)

now the velocity is initially along - Y direction so it is given as


v_i = - 3\hat j

now we know that the acceleration of the particle is given as


\vec a = -3.5 \hat i + 6 \hat j

now when particle will cross Y axis then the displacement in x direction is given as


d_x = 0 - 8 = - 8m

so in x direction we can use kinematics as


d_x = v_(ix) t + (1)/(2) at^2


- 8 = 0 + (-3.5) t^2


t = 1.51 s

User J Del
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