Newton's Second Law: Calculating Net Force on a Wagon with a Child (28.5kg)

[Mathcaptor]

A wagon carries a child. Together mass is 28.5kg. You pull on the handle of the wagon at an angle of 40degrees from the horizontal. The wagon travels over a level horizontal sidewalk. A force of friction of 12.0N acts on the wagon.

a) What is the net force acting on the wagon?



Note: I'm really having trouble with calculating this (triangle wise). Please help ASAP.

 

[Carid]

There's a force W operating vertically downwards. It's the weight of the trolley.
There's a force F pulling on the trolley. All I know about that force is that the horizontal component is sufficient to overcome a 12N frictional force.
So build a right angled triangle with a 40° angle in it to represent the force vectors. The hypotenuse is length F (unknown for the moment). The force adjacent to the 40° angle is length 12. Now can you calculate F?

Then you need to do the vector addition of W and F to find the net force.
The angle between F and W will be 90° + 40°.

 

[thomate1]

I am happy to assist with your question. According to Newton's Second Law, the net force acting on an object is equal to its mass multiplied by its acceleration (F=ma). In this situation, we have a wagon with a mass of 28.5kg and a force of friction acting on it of 12.0N.

To calculate the net force, we need to first break down the force pulling on the wagon into its horizontal and vertical components. The horizontal component of the force pulling on the wagon is equal to Fcos(40) = 15.4N, and the vertical component is equal to Fsin(40) = 18.3N.

Now, we can calculate the net force by subtracting the force of friction from the horizontal component of the pulling force. This gives us a net force of 15.4N - 12.0N = 3.4N.

Therefore, the net force acting on the wagon is 3.4N. This means that the wagon will experience an acceleration in the direction of the net force, which in this case is in the direction of the pulling force at an angle of 40 degrees from the horizontal. I hope this helps with your calculations.