Gold, which has a density of 19.32 g/cm³, is the most ductile metal and can be pressed into a thin leaf or drawn out into a long fiber. (a) If a sample of gold with a mass of 8.338 g, is pressed into a leaf of 1.622 μm thickness, what is the area of the leaf? (b) If, instead, the gold is drawn out into a cylindrical fiber of radius 2.300 µm, what is the length of the fiber?

The nucleus of an atom can be modeled as several protons and neutrons closely packed together. Each particle has a mass of 1.67 x 10-27 kg and radius on the order of 10-15 m. (a) Use this model and information to estimate the density of the nucleus of an atom. 3.986E177 Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. kg/m³ (b) Compare your result with the density of a material such as iron. What do your result and comparison suggest about the structure of matter?

PAGE 316 HOMEWORK CHAPTER 12 7. A ring made of gold (atomic weight 196.967) has a mass of 4.00 g. How many gold atoms are in it? Ans. 1.22 x 1022

Let Pa represent the density of aluminum and Pf that of iron. Find an expression of the radius (ra ) of a solid aluminum sphere that balances a solid iron sphere of radius rf on an equal-arm balance

Assuming biological substances are 100% water, estimate the mass of a fly. Take a fly to be roughly a cylinder 4 mm long and 2 mm in diameter. kg

Flow rate is expressed as gas velocity in cm/s. The gas is flowing through an open tubular column with an inner diameter of 0.25 mm. What volume flow rate (mL/min) corresponds to a gas velocity of 50 cm/s? (The volume of a cylinder is pr2 3 length, where r is the radius.)

Neutron stars consist only of neutrons and have unbelievably high densities. A typical mass and radius for a neutron star might be 2.00 x 1o28 kg and 1.80 x 103 m. (a) Find the density of such a star. 81869826600000, kg/m3 (b) If a dime (V = 2.0 x 10-7m³) were made from this material, how much would it weigh (in pounds)? 1.64 X Ib

Juno is a construction worker. He has found a scrap piece of construction aluminum foil. The sheet has the dimensions of 1.00ft x 5.00ft. Juno knows the 3 aluminum density is 2. 70g/cm. He weighs it and finds its mass is 20.1 grams. Help Juno figure out how thick the sheet is. write your answer in millimeters and with the correct amount of significant figures.

An automobile tire is shown in the figure below. The tire is made of rubber with a uniform density of 1.10 × 103 kg/m³. The tire can be modeled as consisting of two flat sidewalls and a tread region. Each of th sidewalls has an inner radius of 16.5 cm and an outer radius of 30.5 cm as shown, and a uniform thickness of 0.675 cm. The tread region can be approximated as having a uniform thickness of 2.50 cm (that i its inner radius is 30.5 cm and outer radius is 33.0 cm as shown) and a width of 19.4 cm. What is the moment of inertia (in kg m2) of the tire about an axis perpendicular to the page through its center? " 33.0 cm 16.5 cm Sidewall 30.5 cm Tread Enter a number. find the moment of inertia of the sidewall and the moment of inertia of the tread region. Each can be modeled as a cylinder of nonzero thickness. What is the inner and outer radius for each case? What is the formula for the moment of inertia for a thick-walled cylinder? How can you find the mass of a hollow cylinder?…

If the average volume flow of blood through the aorta is 8.50 × 10−5 m3/s and the cross-sectional area of the aorta is 3.00 × 10−4 m2, what is the average speed of blood in the aorta?