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Peter G.
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A stone weight 32 N is attached to a wire and hung from a rigid support. A string is then attached to the bob and is pulled sideways with a horizontal force P until the tension in the wire is 44N
a) What is the angle between the wire and the vertical?
b) Calculate the size of the force P
c) Repeat your calculations for the case when the tension is 140 N
a) cos (32/44) Angle = 43.34
b)44^2 - 32^2 = P ^2
P = 30.20 N
Same methods for c) 77.79 degrees and 136.29 N
Think those are correct?
For the next question, I had a lot of difficulty, so I dealt with the information I had but I don't know if what I did is right: A framed picture of weight 15 N is to be hung on the wall, using a piece of string. The ends of the string are tied to two points, 0.60m apart, on the same horizontal level, on the back of the picture. Draw a free body force diagram for the picture and find the tension in the string if: a) the string is 1.0 m long, b) the string is 0.66 m
So, since the string is tied on the same horizontal level, I think that the length of the string for the left and right sides will be the same, so, for a) 0.50 m and 0.50 m. With that and half of the 0.60 m, I formed a triangle, I managed to find the angle to the vertical. With the angle to the vertical and using the vertical component of tension, I assumed that it was 15/2 for each, thus, 7.5 m I got: T = 7.5/cos 36.86989765, which is = to: 9.38 N
I did the same for part B and got 18.0 N.
What I did is acceptable/correct?
Thanks in advance,
Peter G.
a) What is the angle between the wire and the vertical?
b) Calculate the size of the force P
c) Repeat your calculations for the case when the tension is 140 N
a) cos (32/44) Angle = 43.34
b)44^2 - 32^2 = P ^2
P = 30.20 N
Same methods for c) 77.79 degrees and 136.29 N
Think those are correct?
For the next question, I had a lot of difficulty, so I dealt with the information I had but I don't know if what I did is right: A framed picture of weight 15 N is to be hung on the wall, using a piece of string. The ends of the string are tied to two points, 0.60m apart, on the same horizontal level, on the back of the picture. Draw a free body force diagram for the picture and find the tension in the string if: a) the string is 1.0 m long, b) the string is 0.66 m
So, since the string is tied on the same horizontal level, I think that the length of the string for the left and right sides will be the same, so, for a) 0.50 m and 0.50 m. With that and half of the 0.60 m, I formed a triangle, I managed to find the angle to the vertical. With the angle to the vertical and using the vertical component of tension, I assumed that it was 15/2 for each, thus, 7.5 m I got: T = 7.5/cos 36.86989765, which is = to: 9.38 N
I did the same for part B and got 18.0 N.
What I did is acceptable/correct?
Thanks in advance,
Peter G.