A blimp is filled with 200 m3 of helium. How much mass can the balloon lift? The density of helium is one-seventh that of air, and the density of air is 1/800 that of water. Consider the mass of the balloon to be negligible.
a. 115 kg
b. 214 kg
c. 315 kg
d. 415 kg
e. 37 kg
[Ques. 2] What is the total mass of the Earth's atmosphere? The radius of the Earth is 6.4 106 m, and 1 ATM = 1.01 105 N/m2.
a. 5.3 1016 kg
b. 1.1 1018 kg
c. 5.3 1018 kg
d. 1.1 1020 kg
e. 5.3 109 kg
[Ques. 3] Some species of whales can dive to depths of one kilometer. What is the total pressure they experience at this depth? (sea = 1 020 kg/m3 and 1.01 105 N/m2 = 1 ATM.)
a. 9.00 ATM
b. 90.0 ATM
c. 100 ATM
d. 111 ATM
e. 130 ATM
[Ques. 4] Find the pressure in atmospheres in the water at the base of Dworshak Dam if the water in the reservoir is 200 meters deep. (1.01 105 N/m2 = 1 ATM.)
a. 20.4 ATM
b. 24.7 ATM
c. 29.4 ATM
d. 194 ATM
e. 75 ATM
[Ques. 5] Find the average density of a red giant star with a mass of 20 1030 kg (approximately 10 solar masses) and a radius of 150 109 m (equal to the Earth's distance from the sun).
a. 1.41 104 kg/m3
b. 0.007 kg/m3
c. 1.41 kg/m3
d. 710 kg/m3
e. 1.41 103 kg/m3
[Ques. 6] Find the average density of a white dwarf star if it has a mass equal to that of the sun (2.0 1030 kg) and a radius equal to that of the Earth (6.4 106 m).
a. 9.0 106 kg/m3
b. 1.8 107 kg/m3
c. 1.8 109 kg/m3
d. 3.6 1010 kg/m3
e. 9.0 107 kg/m3
[Ques. 7] All people come very close to being able to float in water. What therefore is the volume (in cubic meters) of a 50-kg woman?
a. 0.007
b. 0.035
c. 0.050
d. 0.070
e. 0.085
[Ques. 8] When water freezes, it expands about nine percent. What would be the pressure increase inside your automobile engine block if the water in there froze? The bulk modulus of ice is 2.0 109 N/m2, and 1 ATM = 1.01 105 N/m2.
a. 18 ATM
b. 360 ATM
c. 1 100 ATM
d. 1 800 ATM
e. 600 ATM
[Ques. 9] A stonecutter's chisel has an edge area of 0.7 cm2 . If the chisel is struck with a force of 42 N, what is the pressure exerted on the stone?
a. 600 N/m2
b. 30 000 N/m2
c. 300 000 N/m2
d. 600 000 N/m2
e. 6 000 N/m2
[Ques. 10] The motion of a piston in an auto engine is simple harmonic. If the piston travels back and forth over a distance of 10 cm, and the piston has a mass of 1.5 kg, what is the maximum speed of the piston and the maximum force acting on the piston when the engine is running at 4 200 rpm?
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