Calculating Horizontal Force for a Shopping Cart on an Inclined Plane

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To calculate the horizontal force needed to push a 7.3 kg shopping cart up a 13° incline with an acceleration of 1.63 m/s², the formula \vec F = m \vec a is applicable. The gravitational force acting on the cart has a component parallel to the incline that must be considered. The horizontal force applied by the shopper also has a parallel component affecting the cart's motion. The sum of these forces parallel to the incline must equal the mass of the cart multiplied by the acceleration. Using these principles will lead to the correct calculation of the required horizontal force.
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What formula do I use?

A shopper pushes a 7.3 kg shopping cart up a 13° incline, as shown in Figure 5-21. Find the horizontal force, F, needed to give the cart an acceleration of 1.63 m/s2.
 

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What formula do I use?

Use \vec F = m \vec a
 
Tide said:
Use \vec F = m \vec a

i did that and got 18.99 N but its being counted as wrong. There are some formulas in my book that show horizontal force as \sum\\F_{x}=F_{1},_{x}+F_{2},_{x}=F_{1}+F_{2}\cos\theta but am not given any forces?? :confused:
 
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You know what the force of gravity is! It's direction is vertical but has a component parallel to the incline. The shopper applies a horizontal force which also has a component parallel to the incline. The sum of the forces parallel to the incline equals mass times acceleration along the incline.

You should be able to take it from there.
 
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