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- Mar 1, 2012

- 935

total length of the box? … maybe the string length is 16 m ?

if so, I get m = 7.5 kg

if so, I get m = 7.5 kg

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- #3

Iam so so sorry again typo error. Its the total length of the rope = 16mtotal length of the box? … maybe the string length is 16 m ?

if so, I get m = 7.5 kg

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- #4

The ans in the textbook says 6 kg.total length of the box? … maybe the string length is 16 m ?

if so, I get m = 7.5 kg

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- #5

Can you pls pls tell me how to work it out?total length of the box? … maybe the string length is 16 m ?

if so, I get m = 7.5 kg

- Mar 1, 2012

- 935

6 kg is correct … I used the wrong value for a trig ratio.The ans in the textbook says 6 kg.

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- #7

Can you pls pls tell me the method you worked it out? I have no clue how to solve it.6 kg is correct … I used the wrong value for a trig ratio.

- Mar 1, 2012

- 935

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- #9

I have no clue how to do it. Sin theta= h/ sq root(h^2+16).

- Mar 1, 2012

- 935

$h + \sqrt{h^2+16} = 8$

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- #11

By squaring both sides I will get 2h^2=-8 .$h + \sqrt{h^2+16} = 8$

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- Mar 1, 2012

- 935

$\sqrt{h^2+16} = 8-h$

square both sides …

$h^2+16 = 64 - 16h + h^2$

$16h = 48$

$h =3$

check solution …

$3 + \sqrt{3^2+16} = 3 + 5 = 8$

checks good.

recommend you review solving radical equations …

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- #13

Thank you so so much!!! None of these things are explained in the textbook. Iam really struggling with the pulley and string questions. I will surely look into solving radical equations.

$\sqrt{h^2+16} = 8-h$

square both sides …

$h^2+16 = 64 - 16h + h^2$

$16h = 48$

$h =3$

check solution …

$3 + \sqrt{3^2+16} = 3 + 5 = 8$

checks good.

recommend you review solving radical equations …