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The density of steel is approximately 7.8 grams per cubic centimeter.
An empty steel can with a mass of 76 grams has a radius of 6.1 centimeters
and a height of 6.3 centimeters.
Estimate the thickness of the steel. Round your answer to the nearest hundredth.
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To estimate the thickness of the steel in this problem, it is ENOUGH to calculate
the surface area, S, of the can.
Then you will write this equation for the mass
S*t*d = 76 grams, (1)
where t is the thickness (which is small and is assumed uniform over the entire surface),
d is the steel density.
This equation contains only one unknown t, which is under the problem's question
and which you will find from equation (1) as
t = . (2)
So, the only thing to work on is to find the surface area of the can.
The radius is 6.1 cm, the height is h= 6.3 cm, = 3.14 (approximately), so the surface area is
S = + = = 475.0192 cm^2,
which you can round to 475 cm^2.
Now the thickness of the material (steel) is, according formula (2)
t = = 0.0205 centimeters,
or, in more appropriate units, 0.2 millimeters. ANSWER
Solved.
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This problem teaches you to apply common sense, along with the school geometry basics.