physics help

Question

Marks: --/2
A 17.9kg box is accelerating down a 35° incline. The coefficient of kinetic friction is 0.53. What is the acceleration of the box? Give your answer . . .
in terms of m/s2. Do not include units in your answer. They will be assumed to be m/s2.
to a precision of tenths of a m/s2. Use a format like ##.# or #.# in your answer.
to an accuracy of 0.2 m/s2. Answers within 0.2 m/s2 of the correct answer will be tolerated.

 

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Answer 1

Weight of of the box = 17.9 * 9.8 = 175.42 newtons

Normal force acting up on the box by the inclined plane = 175.42 * cos(35) = 175.42 * 0.8192 = 143.7041

 

Friction = Normal force * coefficient of kinetic friction = 143.7041 * 0.53 = 76.16315

 

Sum of forces down the inclined plane = 

175.42 * sin(35) - friction = 175.42 * 0.5736 - 76.16315 = 100.6209 - 76.16315 or net force down the plane of

24.45776

 

To calculation acceleration, divide force by mass:

24.45776 / 17.9 = 1.366355 meters per second per second

 

ANSWER: 1.4