Finding displacement with coefficient of friction, mass and velocity

AI Thread Summary
A physics student is calculating the distance a 2.0kg textbook slides before stopping due to friction after being pushed with an initial velocity of 2.70m/s. The coefficient of friction (μ) is 0.20, leading to a frictional force (Ff) of 20N. The net force acting on the book is determined to be -4N, indicating that friction is the only force opposing the motion. The student is trying to find the acceleration caused by friction to apply kinematic equations for distance. Understanding the negative acceleration due to friction is crucial for solving the problem effectively.
Serendipitydo
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Homework Statement


A physics student slides a 2.0kg textbook along the laboratory bench to her friend. She imparts to the book an initial velocity of 2.70m/s. μ=0.20. How far away is her friend if the book comes to a stop right in front of her friend

Vi= 2.70m/s μ=0.20 m=2.0kg Vf= 0m/s d=?

Homework Equations

The Attempt at a Solution


We were taught to figure out everything we could possibly figure out, relevant or not.
FN=Ff (no vertical movement)

Ff=μFN
Ff=(0.20)((2.0kg*9.81m/s2))
Ff=20N

Fnet(Fa-Ff)=ma then use Vf2=Vi2+2ad and solve for d? I just don't know how to find Fa or acceleration with the given variables. Is Fnet equal to Ff in the direction opposite of acceleration/Fa? Does that help?

We haven't done anything with μ and mass combined with velocity to find distance.
 
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Serendipitydo said:

Homework Statement


A physics student slides a 2.0kg textbook along the laboratory bench to her friend. She imparts to the book an initial velocity of 2.70m/s. μ=0.20. How far away is her friend if the book comes to a stop right in front of her friend

Vi= 2.70m/s μ=0.20 m=2.0kg Vf= 0m/s d=?

Homework Equations

The Attempt at a Solution


We were taught to figure out everything we could possibly figure out, relevant or not.
FN=Ff (no vertical movement)

Ff=μFN
Ff=(0.20)((2.0kg*9.81m/s2))
Ff=20N

Fnet(Fa-Ff)=ma then use Vf2=Vi2+2ad and solve for d? I just don't know how to find Fa or acceleration with the given variables. Is Fnet equal to Ff in the direction opposite of acceleration/Fa? Does that help?

We haven't done anything with μ and mass combined with velocity to find distance.
The only equations we have are:
Fnet=ma Fg=mg Ff=μFN
a=(Vf-Vi)/t
Vf2=Vi2+2ad
d=Vit+1/2at2
d=[(Vf+Vi)/2]t
 
The book would keep on sliding along at 2.7 m/sec, except there is a frictional force slowing it down. What is the acceleration (i.e., deceleration) that friction causes to the book? Once you have determined the value for a, the rest is easy.
 
NascentOxygen said:
The book would keep on sliding along at 2.7 m/sec, except there is a frictional force slowing it down. What is the acceleration (i.e., deceleration) that friction causes to the book? Once you have determined the value for a, the rest is easy.
So the acceleration would be negative and friction would influence it. I just don't know what to use to find Fnet, not knowing Fa. Is Fnet -4.0N ? The negative force of friction?
 
Serendipitydo said:
So the acceleration would be negative and friction would influence it. I just don't know what to use to find Fnet, not knowing Fa. Is Fnet -4.0N ? The negative force of friction?
I don't know what you call Fa, but there is only one force acting on the book, and that's friction. The net force acting on the book is -4N.
 
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