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Calculating Initial Velocity for Symmetric Projectile Motion
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In summary, the potato would have a velocity of 3.14 x 10^-6 m/s and an angle of 36.4 degrees when it reaches the top of the screen.
- #2
gneill
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Start by listing kinematic equations that might be useful. What's the maximum height of a launched projectile? How much time does it take to reach its maximum height?
The problem doesn't explicitly say what height the potato may have when it passes over the screen, so I suppose that you could assume that it just clears it at the screen's height.
Hint: can you find the equation for the trajectory of a "reverse" potato launched from the center of the wall opening and just clearing the screen?
The problem doesn't explicitly say what height the potato may have when it passes over the screen, so I suppose that you could assume that it just clears it at the screen's height.
Hint: can you find the equation for the trajectory of a "reverse" potato launched from the center of the wall opening and just clearing the screen?
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doc2142
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I am a bit confused about your hint. a reverse? what is that exactly mean like wouldn't it need a velocity to go from the hole in the wall to the top of the screen?
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gneill
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doc2142 said:
Yup. One property of projectile motion is that its trajectories are "reversible". You can launch a projectile and plot its trajectory to its landing point, and if you note its landing angle and speed, you can launch it from there back along its trajectory by using the same speed and angle to do so.
So what velocity (x and y components) would take a potato from the center of the window to the top of the screen as the trajectory apex?
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JHamm
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Could you simplify this somewhat by removing 10cm of height from everything, setting your axis inline with where the projectile begins? Then perhaps consider the system as symmetric about the screen?
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gneill
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JHamm said:
Yes! Those are two easy simplifications that hardly require any elbow grease to carry out
FAQ: Calculating Initial Velocity for Symmetric Projectile Motion
What is initial velocity?
Initial velocity is the starting velocity of an object in motion. It is the velocity at the beginning of a time period, before any acceleration or deceleration occurs.
How is initial velocity calculated?
Initial velocity can be calculated using the equation v0 = (vf - at), where v0 is the initial velocity, vf is the final velocity, a is the acceleration, and t is the time elapsed.
Can initial velocity be negative?
Yes, initial velocity can be negative. A negative initial velocity indicates that the object is moving in the opposite direction of a chosen positive direction. For example, if we define positive as moving to the right, a negative initial velocity means the object is moving to the left.
What units are used to measure initial velocity?
Initial velocity can be measured in units of distance over time, such as meters per second or feet per second. It can also be measured in units of speed, such as kilometers per hour or miles per hour.
Why is calculating initial velocity important in science?
Calculating initial velocity is important because it allows us to understand the motion of objects and predict their future positions. It is also a key component in determining other factors of motion, such as acceleration and displacement.