Need help with projectile/friction problem.

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Homework Help Overview

The problem involves a scenario where an object is pushed across a table and falls off the edge, requiring the calculation of its initial speed considering the effects of friction and gravitational potential energy.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants discuss the relationship between kinetic energy and gravitational potential energy, and some suggest using equations of motion to relate time of fall to horizontal distance traveled.

Discussion Status

There is an ongoing exploration of different approaches to determine the initial speed of the object. Some participants have provided equations and concepts for consideration, while others emphasize the importance of guiding rather than solving the problem directly.

Contextual Notes

Participants are reminded of the forum rules that restrict helpers from providing complete solutions, focusing instead on guiding the original poster through the reasoning process.

Shipman515
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A popular pastime is to see who can push an object closest to the edge of a table without its going off. You push the 100 g object and release it 3.00 m from the table edge. Unfortunately, you push a little too hard. The object slides across, sails off the edge, falls 1.30 m to the floor, and lands 25.0 cm from the edge of the table.

If the coefficient of kinetic friction is 0.500, what was the object's speed as you released it?

I've tried a lot of different things, suggestions?
 
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I don't know if this will help but have u tried

kinetic energy = gravitational potential energy

1mv^2/2 = mgh
 
t = time to fall
y = vertical distance
g = acceleration (9.8m/s^2)
x = distance traveled off table
v1 = initial speed
v2 = speed as object leaves table (x component)


y = (1/2)*g*t^2 therefore t = (2*y/g)^(1/2)
x = v2*t therefore x = v2*(2*y/g)^(1/2)

Maybe someone can finish this for you. I apologize my laptop is dying:(
 
try to figure out the velocity when it leaves the table and starts falling. If you find it, you can find its kinetic energy at the instant. Since there is friction on the table, the kinetic friction caused the mass to be slowed down from the initial velocity it took off from. how much did it slow down, or how much energy did it lose to friction? If you know that than, you can trace back and find the initial velocity.
 
Last edited:
Please keep in mind that the rules of this forum are that the "helpers" should only guide the OP, not do or work out the solution.

Zz.
 
Got it. Thanks ya'll. really helped.
 

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