Finding initial velocity when given only mass and distance

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SUMMARY

The discussion centers on calculating the initial velocity of a 1.428 kg textbook kicked 183 centimeters. The participant attempted to derive acceleration using the formula fk-ma/W, resulting in an acceleration of 14 m/s². However, the lack of time, acceleration, and force information leads to ambiguity in determining a unique initial velocity. The conversation highlights the importance of understanding the context of the problem, particularly whether the book is kicked vertically or horizontally, as this significantly affects the outcome.

PREREQUISITES
  • Understanding of Newton's Second Law of Motion
  • Familiarity with kinematic equations, specifically Vf² = Vo² + 2aΔx
  • Basic knowledge of forces and mass conversion (1N = 1kg·m/s²)
  • Concept of gravitational force and its impact on motion
NEXT STEPS
  • Study the application of Newton's Second Law in various contexts
  • Learn how to apply kinematic equations in horizontal and vertical motion scenarios
  • Explore the concept of friction and its effect on motion
  • Investigate the role of forces acting on objects in motion, including gravity
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Students studying physics, particularly those focusing on mechanics, as well as educators seeking to clarify concepts related to motion and forces.

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Homework Statement


A 1.428 kg textbook is kicked 183 centimeters, what is the initial velocity right as it left the foot?

Homework Equations



fk-ma/W
Vf^2=Vo^2*2aΔx

The Attempt at a Solution


We were given no time, no acceleration, and no force. I'm completely at a loss!
this is what I have, but I don't think it's correct:
I found acceleration by applying the rule: 1N is a force that when applied to object with mass of 1kg, produces an acceleration of 1 m/s^2. So i converted the 1.428 kg into 14.0 N, which (hopefully) means the acceleration is 14 m/s^2
then I used the second equation to solve for initial velocity.

Now, this could be completely wrong, and I will venture to guess that it is. So if maybe someone could double check the work here, or even possibly come up with a completely different way of solving it..
 
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This problem makes sense if you assume that the book is kicked straight up in the air in which case the mass is irrelevant. If the book slides across a horizontal floor, a higher initial velocity than the expected answer can be compensated by a less slippery floor which means that there is no unique answer. Are you sure you have provided all the information that was given to you?
 
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I second what kuruman said.
However, I'd like to ask you this: what made you think that there's a force other than that of gravity acting on the book?
 

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