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2 years ago

7

in a pickup game of dorm shuffleboard, students crazed by final exams use a broom to propel a calculus book along the dorm hallw

ay. If the 3.5 kg book is pushed from rest through a distance of 0.96 m by the horizontal 22 N force from the broom and then has a speed of 1.36 m/s, what is the coefficient of kinetic friction between the book and floor?

1 answer:

madam [21]2 years ago

3 0

Answer:

μ=0.151

Explanation:

Given that

m= 3.5 Kg

d= 0.96 m

F= 22 N

v= 1.36 m/s

Lets take coefficient of kinetic friction = μ

Friction force Fr=μ m g

Lets take acceleration of block is a m/s²

F- Fr = m a

22 - μ x 3.5 x 10 = 3.5 a ( take g =10 m/s²)

a= 6.28 - 35μ m/s²

The final speed of the block is v

v= 1.36 m/s

We know that

v²= u²+ 2 a d

u= 0 m/s given that

1.36² = 2 x a x 0.96

a= 0.963 m/s²

a= 6.28 - 35μ m/s²

6.28 - 35μ = 0.963

μ=0.151

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In an elastic collision the total linear momentum and the total kinetic energy is conserved.

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Because the linear momentum is a vector quantity we consider the conservation of the components of momentum in the x and y axis.

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