Solving Two Body Problems - The Physics Classroom

[RiskX]

Hi,

I'm currently learning how to solve two body problems and I'm having a little trouble with that. My question regards a certain example I found in The Physics Classroom website that goes like this:

"A 5.0-kg and a 10.0-kg box are touching each other. A 45.0-N horizontal force is applied to the 5.0-kg box in order to accelerate both boxes across the floor. Ignore friction forces and determine the acceleration of the boxes and the force acting between the boxes."

I managed to find out the acceleration(3 m/s/s) but I don't understand how to find the force acting between the boxes. In the solution of this example they took the 10 kg boy and just calculated it's net force(30 N) and I undertood that but if I to calculate the net force acting on the 5 kg(15 N) body I'll get a different result entirly.

How can I determine the force acting between the boxes using the 5 kg box alone.

Thanks!

 

[Spinnor]

See the attached,

 

[RiskX]

I'm sorry but I bealive you forgot the attachment...

 

[Spinnor]

Right, sorry %^) And I normally preview stuff.

 

[rwisz]

I would like to first clarify that solving two body problems involves applying Newton's laws of motion and using mathematical equations to determine the motion of two interacting objects. In this case, the example you provided involves finding the acceleration and force acting between two boxes.

To find the force acting between the boxes, we need to consider the concept of action-reaction pairs. According to Newton's third law, for every action, there is an equal and opposite reaction. In this case, when the 45.0-N horizontal force is applied to the 5.0-kg box, the 5.0-kg box exerts an equal and opposite force on the 10.0-kg box. This force is the force acting between the boxes.

To calculate this force, we can use the equation F=ma, where F is the force, m is the mass, and a is the acceleration. In this case, the mass of the 5.0-kg box is 5.0 kg, and the acceleration is 3 m/s/s. Therefore, the force acting between the boxes is 5.0 kg x 3 m/s/s = 15 N.

The solution provided on The Physics Classroom website may have calculated the net force on the 10.0-kg box because it is easier to visualize and understand. However, both approaches should lead to the same result, as long as Newton's laws of motion are applied correctly.

I hope this explanation helps to clarify your understanding of how to determine the force acting between two boxes in a two body problem. Keep practicing and applying these concepts, and you will become more proficient in solving these types of problems.