Projectile motion velocity homework

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To find the velocity of the projectile 1.50 seconds after firing, first calculate the vertical component of velocity using the formula Vy = Vy initial - g*t, where g is the acceleration due to gravity (9.8 m/s²). After determining the vertical velocity at 1.50 seconds, combine it with the constant horizontal velocity (Vx = 62 m/s) to find the total velocity. The horizontal component remains unchanged because there is no air resistance in the vacuum assumption. The final velocity can be expressed as a vector combining both components.
ruthi
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my problem says:
a projectile is fired with an initial speed of 75.2 m/s at an agle of 34.5 degrees above the horizontal on a long flat firing range. i figured out everyting so that

y initial = 0
y = 92.6m
Vy initial = 42.6 m/s
Vy = 0
g = 9.8 m/s^2
t = 8.69 s
Vx = 62 m/s

the question asks for the volocity of the projetile 1.50 s after firing. how do you go about figuring that out?
 
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Assuming a vacuum here, and a flat earth, the horizontal component remains constant, so you can ignore it for the moment, and concentrate on the vertical component of velocity and acceleration (which only has a vertical component anyway in this case). After you've done this, then re-include the horizontal component of velocity.
 
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