rescue lab 7

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course Phy 201

Projectile (near horizontal)Uses steel ball, ramp, rulers, carbon paper (optional but desirable), dominoes

Support the long ramp with a domino on its flat edge.

Determine the horizontal projectile range of the ball when released from the very edge of the ramp.

Spacing the ball from the edge of the ramp by 1, 2 and 3 domino thicknesses, then by 1, 2, 3, 4 and 5 domino lengths, determine its projectile range.

Give your data:

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edge= 4.5cm

1 thick= 4.6cm

2 thick= 4.9cm

3 thick= 5.2cm

1 length= 5.5cm

2 length= 6.1cm

3 length= 6.9cm

4 length= 7.2cm

5 length= 8.3cm

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Graph projectile range vs. distance down the ramp. Describe the shape of your graph.

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The graph formed a very close to linear shape with a positive slope.

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Based only on the points corresponding to 3, 4 and 5 domino lengths, state whether it appears that the horizontal range is proportional to the number of domino lengths.

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I believe the range is proportional to the number of dominoe lengths. Since I picked the paper up each time to record the length, the paper could have been in different positions and cause the error.

6.9cm/15cm= 0.46

7.2cm/20cm= 0.36

8.3cm/25cm= 0.33

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Analysis:

Determine the time of the ball's fall.

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Find the horizontal velocity of the falling ball for each trial, assuming its initial vertical velocity to be negligible.

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Assuming ball mass to be 60 grams, find for each trial its kinetic energy at the instant it left the ramp.

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For each trial, figure out how much potential energy the ball lost between release and the edge of the ramp. You can follow the reasoning introduced in the Edge Effect experiment.

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Make a table of KE vs. `dPE, where KE is the kinetic energy at the instant the ball left the ramp and `dPE is the potential energy it lost between release and edge.

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A number of things are a bit 'fishy' about the analysis as outlined here. A number of effects were sort of glossed over. If anything didn't seem quite right to you, this would be a good place to show off your insight. This is optional so you have nothing to lose.

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Good data. You can proceed with the analysis.