ANOTHER Question PHYSics this time lols (1 Viewer)

super.muppy

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find da lenghts of x and y plus working out plz
lols please have a go if u noe plz thanks
i tried for a long time srsly:hammer:
 

youngminii

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What the random~
What is this? The picture doesn't tell us much
 

acevipa

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This is a tough question. What you have to do is add some information to the diagram.

View attachment 17755

Notice that the dotted line and the solid line are parallel, therefore alternate angles are equal.

Now, imagine that you have something on the end of a string which has a force of 200 N downwards. It has to be in equilibrium. So the addition of the horizontal forces must equal 0.

However, the addition of the vertical forces must equal 200 N, as the object (which has a force of 200 N) is in equilbrium. Hence the downwards force (which is 200 N) must equal the total upwards force (T1y + T2y = 200)

So therefore:

T1x = T2x (1)
T1y + T2y = 200 (2)

Now that we have two simultaneous equations, we can use trigonometry now to form several equations.

sin 26° = T1y / T1
Therefore, T1y = T1 sin 26°

Repeat that for the rest:

sin 45° = T2y / T2
Therefore, T2y = T2sin 45°

cos 26° = T1x / T1
Therefore, T1x = T1cos 26°

cos 45° = T2x / T2
Therefore, T2x = T2cos 45°

Substitute these values into the original simulataneous equations.

T1cos 26° = T2cos 45° (1)
T1 sin 26° + T2sin 45° = 200 (2)

Therefore solve simultaneously:

T1cos 26° = 1/√2 T2
T1 sin 26° + 1/√2 T2 = 200

Therefore:

T1 sin 26° + T1cos 26° = 200
T1(sin 26° + cos 26°) = 200

Therefore T1 = 149.57 N

Now sub T1 into one of the equations to find T2

Therefore T2 = 190.12 N
 
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super.muppy

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THANKS acevipa i owe u one. my phys teacher set it as an extension question :( rewarding who ever gets it with a prize :) many thanksssss
 

cutemouse

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This is like 4U Mechanics. I think it was in the old course.

My old Physics teacher was so hopeless that, he suggested using actual rulers protractors to draw/measure these vector force diagrams.

He didn't have a clue of the sine/cosine rule :p
 

rereader

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Cosine rule is good to remember. I guess your Physics teacher must be 70, JM. Before hand held calculators (1970s) drawing was the usual way to solve these - to 3 significant figures. It's pretty quick.
 

cutemouse

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rereader said:
I guess your Physics teacher must be 70, JM.
Yeah his IQ maybe is...

No he's about 30 or so. Clueless. Lucky I don't have him next year.
 

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