Projectile Motion: Calculating Range, Maximum Height, Speed & Angle

AI Thread Summary
The discussion focuses on solving a projectile motion problem involving a projectile fired into the air. The horizontal range and maximum height have been calculated as 56 m and 49 m, respectively. To determine the speed just before impact, the horizontal component of velocity remains constant at 8.8 m/s, while the vertical component can be found using kinematic equations. The final vertical velocity is influenced by gravitational acceleration, and the angle of motion before impact can be calculated using the tangent of the vertical and horizontal velocities. Understanding these components is essential for completing the calculations for speed and angle.
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Urgent! projectile motion

Heyy every1
Q Exactly 2.7s after a projectile is fired into the air from the ground ,it is observed to have a velocity v = (8.8i+4.5 j) m/s where the x-axis is horizontal and the y-axis is positive upward .
a)Determine the horizontal range of the projectile
b)Determine the maximum height above the ground
c)Determine the speed of motion just above the projectile strikes the ground .
d)Determine the angle of the motion just before the projectile strikes the ground .

I managed to do the first two parts where max height is 49m and range is 56 m .Bt i do not noe how to go abt the c) and d) part
 
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What is horizontal component of the velocity? What is the vertical component of final velocity?
 


well i was able to calaculate the max height and range using horizontal velocity to be 8.8 and vertical final velocity as 4.5 at 2.7 s .This much information only was given n the question tht s why i m confused
 


For d), knowing the horizontal and vertical components of initial velocity should help you. You know that the trajectory is parabolic and so just prior to impact, use the condition,-v_{fy} \hat{y} = v_{oy} \hat{y}.
 


Horizontal velocity(i component) remains constant since no forces acting on it.
Vertically(j component) there is negative acceleration.
Sketch a graph of velocity vs. time. Upward as positive.
Δv/Δt is constant. You can find initial vertical velocity from acceleration equation.

Speed it the vector sum of vertical and horizontal velocity.

Angle of projection is just the tangent of vertical and horizontal velocity.
 
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