Finding the force given the mass and radius.

AI Thread Summary
To find the force given mass and radius, it's essential to consider all forces acting on the object, not just one. A free body diagram is recommended to visualize these forces clearly. In the case of a roller-coaster car, two forces must be accounted for to arrive at the correct answer. The discussion emphasizes the importance of a comprehensive approach to problem-solving in physics. Understanding all contributing factors is crucial for accurate calculations.
ilc
Messages
3
Reaction score
0
The attachment shows my approach to this problem, however, the answer is incorrect.

can anyone explain to me how i should be thinking of this problem?
 

Attachments

  • Capture.JPG
    Capture.JPG
    38.8 KB · Views: 503
Physics news on Phys.org
ilc said:
The attachment shows my approach to this problem, however, the answer is incorrect.

can anyone explain to me how i should be thinking of this problem?
attachment.php?attachmentid=51318&d=1348976198.jpg

Hello ilc. Welcome to PF!

Draw a free body diagram for the roller-coaster car.

There are two forces acting in the car.

You only accounted for one of them.
 
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...
Back
Top