Ugh I just don't get this stuff. The question goes: A 1000 kg steel beam is supported by two ropes in a V shape coming off the center of the beam. The bottom of the "V" is a 60 degree angle. Each of the ropes can support 5600 N max. Do the ropes break?
I don't know what equation I'm supposed to use...
I don't know what equation I'm supposed to use...
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The weight of the beam is given by:
w = mg = (1000 kg)(9.8 m/s²) = 9800 N
We'll do the rest with symmetry. Just look at half the picture since it's the same on both sides.
The y-components are all you really need to worry about for this. The y-component going upwards should be the same as the y-component going downward. The upward component is:
Tsin(60º) .......... I'll let you try to figure out why
But remember we're using symmetry so it'll be:
2Tsin(60º)
The downward y-component is the weight:
9800 N
So these have to be equal or equal the beam will fall or be pulled upward:
2Tsin(60º) = 9800 N
T = 9800 N / 2sin(60º) = 5658 N
Since 5656 N > 5600 N, yes the rope would break.
w = mg = (1000 kg)(9.8 m/s²) = 9800 N
We'll do the rest with symmetry. Just look at half the picture since it's the same on both sides.
The y-components are all you really need to worry about for this. The y-component going upwards should be the same as the y-component going downward. The upward component is:
Tsin(60º) .......... I'll let you try to figure out why
But remember we're using symmetry so it'll be:
2Tsin(60º)
The downward y-component is the weight:
9800 N
So these have to be equal or equal the beam will fall or be pulled upward:
2Tsin(60º) = 9800 N
T = 9800 N / 2sin(60º) = 5658 N
Since 5656 N > 5600 N, yes the rope would break.