Analyzing Forces on a Moving System: Newton's Second Law in Action

In summary, the conversation discusses a homework question involving a system with a total mass of 85 kg and a given force in the x-direction. It is mentioned that the acceleration in the x-direction is correct and the acceleration in the y-direction must also be considered. The next steps involve drawing a free body diagram and using Newton's laws in both the x and y directions to find the normal forces.
  • #1
mathmannn
15
0

Homework Statement



I attached the photo of the question that has everything.

Homework Equations



[itex] F=ma [/itex]

The Attempt at a Solution



So I found the total mass of the system 50+35 = 85. Since we are given the force in the x-direction I used [itex] \frac{70}{85} = a = .8235 [/itex]. The weight of the cylinder is 50*g = 490 N, and weight of the cart is 35*g = 343 N. But I don't know where to go from there. I know that the reaction at A will be larger than at B because the "pulling" force will cause the cylinder to push more on the left side of the cart.. But I don't know how to relate anything to get useful equations.
 

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  • #2
Your acceleration calc in the x directon is correct. The cylinder must also move at that same acceleration in the x direction. What is the cylinder's acceleration in the y direction? You must draw a free body diagram of the cylinder and identify the forces acting on the cylinder in the x and y directions. In what direction do the normal forces act? Then use Newton's laws in the x and y direction.
 

What is Newton's 2nd law of motion?

Newton's 2nd law of motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This means that the larger the force applied to an object, the greater its acceleration will be. Conversely, the greater the mass of an object, the smaller its acceleration will be.

What is the formula for Newton's 2nd law?

The formula for Newton's 2nd law is F=ma, where F is the force applied to the object, m is the mass of the object, and a is the acceleration of the object.

How is Newton's 2nd law related to inertia?

Newton's 2nd law is closely related to the concept of inertia, which is an object's tendency to resist changes in its state of motion. According to the 2nd law, the greater the mass of an object, the greater its inertia will be, meaning it will require a larger force to accelerate it.

Can Newton's 2nd law be applied to objects in motion?

Yes, Newton's 2nd law can be applied to objects in motion as well as objects at rest. In fact, it is often used to calculate the forces acting on an object to determine its motion, such as in projectile motion or circular motion.

How does Newton's 2nd law apply to real-world scenarios?

Newton's 2nd law has many real-world applications, such as understanding the motion of objects on Earth and in space, designing vehicles and structures, and predicting the behavior of materials under stress. It is also the basis for the design and functioning of many everyday objects, from cars and airplanes to sports equipment and amusement park rides.

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