The following are questions from my test which i got wrong.. need help solving them :(adsbygoogle = window.adsbygoogle || []).push({});

q1) Octane, a substance found in petroleum, boils at 126 Celcius and is a liquid over a range of 183 celcius degrees. What is the melting point of octane in kelvins?

I subtracted ( 183 - 126 ) and got 57 degrees celcius as my answer.. and converted that into K.. however, checked the answer and im supposedly supposed ot get -57 and convert that to K... anyone know how to answer this question ? thanks

q2) A 75 kg solid cylinder, 2.5 m long and with an end radius of 5 cm, stands on one end. How much pressure does it exert?

I first found the area of the cylinder by adding AREA OF THE CIRCLE + AREA OF RECTANGLE and got 2.57x10^-1 m^2 ...

I used eq = P = f/a ..

p = 75x9.8/ 2.57x10^-1 = 2.85x10^3 PA..

however, it turns out that this isnt correect for some reason... can anyone please temme why?

q3) A metal object is suspended from a spring scale. The scale reads 920 N when the object is suspended in air and 750 N when the object is completely submerged in water ( density = 1000 kg/m^3)

A) Find the volume of the object

B) Find the density of the metal

for A, i used the equation Fb= pVg but turns out that the answer i got was wrong

For B, i used p=fB/VG...

Q4) How do i convert g/cm3 to kg/m3?

thanks much

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# Homework Help: Help needed to solve this

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