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Assuming a paperback book has a mass of 2.0 kg, a length of 27.0 cm, a width of 21.0 cm, and a thickness of 4.5 cm, what pressure, in Pascals, does it exert on a surface if it is: a) Lying flat? b) Standing on edge in a bookcase?

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Final answer:

The pressure exerted by a 2.0 kg paperback book lying flat is 345.7 Pa, while the pressure when the book is standing on edge is 2074 Pa.

Step-by-step explanation:

The pressure exerted by an object is calculated by dividing the force it applies (its weight in this case) by the area over which the force is distributed. For a paperback book with a mass of 2.0 kg, we first need to calculate the force it exerts due to gravity (its weight), which is the mass times the acceleration due to gravity (F = m * g). Assuming g = 9.8 m/s2, the force is F = 2.0 kg * 9.8 m/s2 = 19.6 N.

a) Lying flat: The area (A) when the book lies flat is the length times the width, A = 27.0 cm * 21.0 cm, which needs to be converted into square meters (0.27 m * 0.21 m = 0.0567 m2). The pressure (P) is then P = F / A = 19.6 N / 0.0567 m2 = 345.7 Pa (rounded to three significant figures).

b) Standing on the edge: The area is now the width times the thickness, which is A = 21.0 cm * 4.5 cm = 0.21 m * 0.045 m = 0.00945 m2. The pressure is thus P = F / A = 19.6 N / 0.00945 m2 = 2074 Pa (rounded to four significant figures).

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