Non-Equilibrium Applications of Newtons Laws

AI Thread Summary
The discussion revolves around calculating the acceleration of two blocks connected by a cord over a pulley, with specific weights given for each block. The weight of the block on the table is 388 N, while the hanging block weighs 175 N. A participant notes that the net force on the hanging block is incorrectly calculated as just the gravitational force, failing to account for additional forces acting on it. The hint suggests that another force is preventing the hanging block from falling freely. Understanding these forces is crucial for accurately determining the system's acceleration and the tension in the cord.
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1. In the drawing, the weight of the block on the table is 388 N and that of the hanging block is 175 N. Ignore all frictional effects, and assuming the pulley and the cord to be massless. Find the acceleration of the two blocks as well as the tension in the cord


2. Fnet = mass of the object * acceleration



3. The force acting on the hanging block is gravity which has a magnitude of 9.8 m/s/s, and the mass is 17.86 kg. So the net force, which is just equal to the gravitational force, would be 175 N, which is incorrect. What am I doing wrong?
 

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There is another force acting on the hanging block. Do you see what it is, from looking at the diagram?

Hint: what stops the hanging block from falling as if it were dropped?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
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