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Does anyone knows how to solve problem 8 on page 130??

>> In fig. a horizontal force of 100N is to be applied to a 10kg slab that is initially stationary on a frictionless floor, to accelerate the slab. A 10kg block lies on top of the slab;

the coeffitiont of the friction (mu) between the block and the slab is not known,

and the block might slip

(a) considering that possibility, what is the possible range of values for the magnitude

of the slab's acceleration?

(b) what is the possible range for the magnitude a of the block's acceleration?

F=(mu)*Normal Force

F=ma

>>I thought like... when the net force of the block is less than the fiction,

the block and the slab move together....

so (a) slab's acc. is ..

F= (M+m)a (when moving together)

a=5m/s^2

F-f(friction)=m(slab's mass)a

100-(mu)*(blockmass)*(g)=ma

answer: 5<a<(100-mu*blockmass*g/m) ??????????

(b)

block's acceleration

5m/s^2 (when moving together)

f(friction)=ma

a=mu*g

mu*g<a<5??

I'm totally stuck in this problem ...

can anyone help me???

** picture included

## Homework Statement

>> In fig. a horizontal force of 100N is to be applied to a 10kg slab that is initially stationary on a frictionless floor, to accelerate the slab. A 10kg block lies on top of the slab;

the coeffitiont of the friction (mu) between the block and the slab is not known,

and the block might slip

(a) considering that possibility, what is the possible range of values for the magnitude

of the slab's acceleration?

(b) what is the possible range for the magnitude a of the block's acceleration?

## Homework Equations

F=(mu)*Normal Force

F=ma

3. The Attempt at a Solution3. The Attempt at a Solution

>>I thought like... when the net force of the block is less than the fiction,

the block and the slab move together....

so (a) slab's acc. is ..

F= (M+m)a (when moving together)

a=5m/s^2

F-f(friction)=m(slab's mass)a

100-(mu)*(blockmass)*(g)=ma

answer: 5<a<(100-mu*blockmass*g/m) ??????????

(b)

block's acceleration

5m/s^2 (when moving together)

f(friction)=ma

a=mu*g

mu*g<a<5??

I'm totally stuck in this problem ...

can anyone help me???

** picture included

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