Projectiles question: acquiring initial velocity from force+mass

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To calculate the initial velocity of a marble launched from a marble launcher, the force must be broken down into horizontal and vertical components. The user correctly calculated these components as Fx=4.83 N and Fy=1.29 N. They then determined the initial accelerations using F=ma, resulting in Ax=483 m/s² and Ay=129 m/s². However, the discussion highlights the importance of the duration for which the force acts on the marble, as this time factor is crucial for determining the actual initial velocities. Without knowing the time of force application, the initial velocities cannot be accurately calculated.
rootoftwo
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Hello, this may be a rather simple question but it's beginning to irritate me: If I were launching a marble of, say, 10g (0.010 kg) from a marble launcher with a force of 5N (tell me if this is realistic or not) at an angle of 15 degrees then how would I go about finding the initial velocity of the marble?

Please tell me if I was taking to this question in the correct manner:
I first split the force F into it's horizontal and vertical components:
Fx=5*cos15
Fx=4.83
Fy=5*sin15
Fy=1.29

I then found, using F= m * a, the initial horizontal and vertical acceleration:
Ax = 483
Ay = 129

This is the point I was truly having trouble with, finding the initial vertical and horizontal velocities:

To do this, I assumed that since the initial velocity are found at the moment all of the force is transferred to the marble:

Vx = Ax
Vy = Ay

Is this true?
 
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You are missing a key number which is how long the force acts on the marble. The longer it acts the higher the initial velocity upon launch. That's because acceleration is a=F/m and v = at = Ft/m.
 
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