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3 years ago

15

A box of bananas weighing 40 N rests on a horizontal surface. The coefficient of static friction between the box and the surface

is 0.4, and the coefficient of kinetic friction is 0.2. If no horizontal force is applied to the box and the box is at rest, how large is the friction force exerted on the box?
8 N

16 N

6 N

0 N

1 answer:

ale4655 [162]3 years ago

3 0

Answer:

$0.4x40 \div 0.2 = 80$

8N

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Answer:

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From the question we are told that

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Answer:

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z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{75-70}{\frac{15}{\sqrt{25}}}=1.67$

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