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course Phy 201
7/1 11 pm
A ball rolls off the end of an incline with a vertical velocity of 20 cm/s downward, and a horizontal velocity of 80 cm/s. The ball falls freely to the floor 120 cm below.•For the interval between the end of the ramp and the floor, hat are the ball's initial velocity, displacement and acceleration in the vertical direction?
Initial Velocity = 20 cm/s
Ds = 0 cm
a = 9.8 m/s^2
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• What therefore are its final velocity, displacement, change in velocity and average velocity in the vertical direction?
• V = V0 + at
• V = 20 cm/s + (9.8 m/s^2)(???? I can’t find any formulas that don’t require time, which is not given
• Ds = 120 cm
• A = 9.8 m/s^2
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See my notes from an earlier problem in which you encountered the same difficulty.
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• What are the ball's acceleration and initial velocity in the horizontal direction, and what is the change in clock time, during this interval?
• V0 = 80 cm/s
Dh = Vh*t
Dh = 80 cm/s * 0s = 0
There is no change in clock time, since you are calculating the initial velocity, which occurs at time zero.
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• What therefore are its displacement, final velocity, average velocity and change in velocity in the horizontal direction during this interval?
• ???? I’m not sure how to get the time, which is essential to get the other figures.
• To calculate the final velocity, I would use the formula vf = v0 + at. I would plug in the values for v0 and a, but since I don’t know how to determine t, I cannot proceed.
• To calculate the average velocity, I would use the formula a = (v - v0) / t, convert it to v = at + v0, and plug in my values for a and v0, since I don’t know how to get time, I cannot solve for v.
• Since I can’t find the final velocity, I can’t subtract the initial velocity from it to find hthe change in velocity.
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• After the instant of impact with the floor, can we expect that the ball will be uniformly accelerated?
• Yes
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• Why does this analysis stop at the instant of impact with the floor?
Balls can bounce in different directions or be otherwise affected by environmental factors.
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