Kinematics/Vectors Homework: Initial Velocity, Acceleration, Speed & Direction

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The discussion revolves around calculating the final speed and direction of a particle with given initial velocities and accelerations. The particle has an initial horizontal velocity of 2.6 m/s and an upward velocity of 3.5 m/s, with horizontal acceleration of 1.3 m/s² and downward acceleration of 1.2 m/s². Participants emphasize treating horizontal and vertical components separately and applying the kinematic equation for final velocity. After calculating the components, the direction of the resultant velocity can be determined using trigonometric principles. The original poster successfully solved the problem and confirmed they obtained the correct answer.
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Homework Statement



A particle has an initial horizontal velocity of 2.6 m/s and an initial upward velocity of 3.5 m/s. It is then given a horizontal acceleration of 1.3 m/s^2 and a downward acceleration of 1.2 m/s^2.

What is its speed after 2.2 s?

What is the direction of its velocity at this time with respect to the horizontal (answer between -180º and +180º)


Homework Equations



all kinematic equations


The Attempt at a Solution



i'm lost on this one
 
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Welcome to PF.

Acceleration is a vector. Velocity is a vector.

You can treat the horizontal and vertical components separately.

You know for instance that Final Velocity is equal to Initial velocity + acceleration times time. Vf = Vi + a*t

Once you determine your components of the resulting Velocity ... combine ... you're done.
 
You are going to end up with 2 final velocities, one in the x and one in the y.

So to find the direction from the positive x axis, take triangles into consideration. You'll have an x component and a y component so you can easily solve for the direction with respect to the horizontal.
 
thanks, i solved and got the right answer
 
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