Question: A block of wood has specific gravity 0.80. When placed in water, what percent of the volume of the wood is above the surface? (20%)
Answer Options:
10%
20%
30%
40%
Answer: 20%
Chapter 554
Question: A steel wire, 150 m long at 10°C, has a coefficient of linear expansion of 11 x 10⁻⁶/°C. Find its change in length as the temperature changes from 10°C to 45°C. (5.8 cm)
Answer Options:
3.2 cm
4.5 cm
5.8 cm
7.0 cm
Answer: 5.8 cm
Question: A rectangular steel plate with dimensions of 30 cm x 25 cm is heated from 20°C to 220°C. What is its change in area? (Coefficient of linear expansion for steel is 11 x 10⁻⁶/°C.) (3.3 cm²)
Answer Options:
2.0 cm²
3.3 cm²
4.5 cm²
6.0 cm²
Answer: 3.3 cm²
Question: A brass cube, 10 cm on a side, is raised in temperature by 200°C. The coefficient of volume expansion of brass is 57 x 10⁻⁶/°C. By what percentage does volume increase? (1.1%)
Answer Options:
0.5%
1.1%
1.5%
2.0%
Answer: 1.1%
Question: An automobile gas tank is filled to its capacity of 15.00 gallons with the gasoline at an initial temperature of 10°C. The automobile is parked in the sun causing the gasoline’s temperature to rise to 60°C. If the coefficient of volume expansion for gasoline is 9.6 x 10⁻⁴/°C, what volume runs out the overflow tube? Assume the change in volume of the tank is negligible. (0.72 gallons)
Answer Options:
0.50 gallons
0.72 gallons
0.80 gallons
1.0 gallons
Answer: 0.72 gallons
Question: A spherical air bubble originating from a scuba diver at a depth of 18.0 m has a diameter of 1.0 cm. What will the bubble’s diameter be when it reaches the surface? Assume constant temperature. (1.4 cm)
Answer Options:
1.0 cm
1.2 cm
1.4 cm
1.6 cm
Answer: 1.4 cm
Question: A tank with a volume of 0.150 m³ contains 27.0°C helium gas at a pressure of 100 atm. How many balloons can be blown up if each filled balloon is a sphere 30.0 cm in diameter at 27.0°C and absolute pressure of 1.20 atm? Assume all the helium is transferred to the balloons. (884 balloons)
Answer Options:
500 balloons
700 balloons
884 balloons
1,000 balloons
Answer: 884 balloons
Question: An inventor develops a stationary cycling device by which an individual, while pedaling, can convert all of the energy expended into heat for warming water. How much mechanical energy is required to increase the temperature of 300 g of water (enough for 1 cup of coffee) from 20°C to 95°C? (1 cal = 4.186 J, the specific heat of water is 4 186 J/kg·°C) (94 000 J)
Answer Options:
75 000 J
80 000 J
94 000 J
100 000 J
Answer: 94 000 J
Question: A 3.00-g lead bullet is traveling at a speed of 240 m/s when it embeds in a wood post. If we assume that half of the resultant heat energy generated remains with the bullet, what is the increase in temperature of the embedded bullet? (specific heat of lead = 0.030 5 kcal/kg·°C, 1 kcal = 4 186 J) (113°C)
Answer Options:
100°C
113°C
120°C
130°C
Answer: 113°C
Question: A swimming pool heater has to be able to raise the temperature of the 40 000 gallons of water in the pool by 10.0°C. How many kilowatt-hours of energy are required? (One gallon of water has a mass of approximately 3.8 kg and the specific heat of water is 4 186 J/kg·°C.) (1 770 kWh)
Answer Options:
1 500 kWh
1 770 kWh
2 000 kWh
2 500 kWh
Answer: 1 770 kWh
Question: A solar heated house loses about 5.4 x 10⁷ cal through its outer surfaces on a typical 24-h winter day. What mass of storage rock is needed to provide this amount of heat if it is brought up to initial temperature of 62°C by the solar collectors and the house is maintained at 20°C? (Specific heat of rock is 0.21 cal/g·°C.) (6 100 kg)
Answer Options:
5 000 kg
6 100 kg
7 000 kg
8 000 kg
Answer: 6 100 kg
Question: A 0.2-kg aluminum plate, initially at 20°C, slides down a 15-m-long surface, inclined at a 30° angle to the horizontal. The force of kinetic friction exactly balances the component of gravity down the plane so that the plate, once started, glides down at constant velocity. If 90% of the mechanical energy of the system is absorbed by the aluminum, what is its temperature increase at the bottom of the incline? (Specific heat for aluminum is 900 J/kg·°C.) (0.07°C)
Answer Options:
0.05°C
0.07°C
0.10°C
0.15°C
Answer: 0.07°C
Question: A puddle holds 150 g of water. If 0.50 g of water evaporates from the surface, what is the approximate temperature change of the remaining water? (L_v = 540 cal/g) (-1.8°C)
Answer Options:
-1.5°C
-1.8°C
-2.0°C
-2.5°C
Answer: -1.8°C
Question: Iced tea is made by adding ice to 1.8 kg of hot tea, initially at 80°C. How many kg of ice, initially at 0°C, are required to bring the mixture to 10°C? (L_f = 3.33 x 10⁵ J/kg, c_w = 4 186 J/kg·°C) (1.4 kg)
Answer Options:
1.0 kg
1.2 kg
1.4 kg
1.6 kg
Answer: 1.4 kg