Mass, weight, density and model limits

9.A shopkeeper pours rice into a dish that hangs from a spring balance. He records the reading. A customer buys some pasta. The shopkeeper notices that the reading on the spring balance, with just pasta in the dish, is the same as it was with just rice in the dish. Which quantity must be the same for the rice and for the pasta?

10.A student determines the density of an irregularly shaped stone. The stone is slowly lowered into a measuring cylinder partly filled with water. Which other apparatus does the student need to calculate the density of the irregularly shaped stone?

11.An object has a mass of 4.0 kg on Earth, where the acceleration of free fall is 9.8 m/s². The object is taken to the Moon, where the acceleration of free fall is 1.6 m/s². Which row gives the correct mass and weight of the object on the Moon?

12.Which piece of equipment is used to measure the mass of an object?

13.A baker uses a balance to weigh out some ingredients to make bread. She weighs out some white flour, then she weighs out some wholemeal flour. She notices that the reading on the balance is the same for both types of flour. The baker can conclude that the two flours have the same:

14.A measuring cylinder is weighed empty, then weighed again containing a liquid. The empty cylinder has a mass of 30 g. The cylinder with liquid has a mass of 93 g and the liquid volume is 20 cm³. What is the density of the liquid?

15.A geologist wants to determine the density of a cone-shaped rock sample. What needs to be known in order to calculate its density?

16.Two beams have the same rectangular cross section, but one is longer than the other. Both beams are made from the same material. Which quantity is the same in both beams?

17.A student wants to measure the density of a piece of rock. She starts by measuring its mass, and finds that it is 2500 g. Next she puts 500 cm³ of water into a large measuring cylinder, then adds the rock. The level in the measuring cylinder rises to 800 cm³. What is the density of the rock?

18.Some unknown liquid in a beaker has a mass of 200 g and a volume of 230 cm³. The density of water is 1.0 g/cm³. How does the density of the unknown liquid compare with the density of water?

19.A lump of butter has a volume of 350 cm³ and a mass of 319 g. What is the density of the butter?

20.A cube of side length 5 cm is placed on a mass balance. The balance reads 128 g. What is the density of the cube?

21.An astronaut has a mass of 80 kg on the Earth. The gravitational field strength on the Moon is 1.6 N/kg. What is the weight of the astronaut on the Moon?

22.The density of a block of wood is 2.7 g/cm³ and a mass of 583.8 g. What is its volume?

23.Two objects P and Q are placed in a beaker containing a liquid. Object P floats in the liquid and object Q sinks. Which row for the densities of object P, object Q and the liquid is possible?

24.A measuring cylinder contains 30 cm³ of a liquid. Some more of the liquid is added until the liquid level reaches the 50 cm³ mark. The reading on the balance increases by 30 g. What is the density of the liquid?

25.A space rocket travels to the Moon. The acceleration of free fall is greater on the Earth than it is on the Moon. How do the mass and weight of the space rocket on the Moon compare with their values on the Earth?

27.A teacher has two blocks of the same material. Block A has a mass of 200 g and a volume of 100 cm³. Block B has a mass of 400 g. What is the volume of block B?

28.A student measures the mass of a liquid as 250 g and its volume as 200 cm³. She then pours out half the liquid. What is the density of the remaining liquid?

29.An object has a weight of 50 N on Earth where g = 10 N/kg. What is its mass?

30.A piece of metal has a density of 8.9 g/cm³ and a volume of 10 cm³. It is cut into two equal halves. What is the density of one half?

31.Calculate the weight of a 5.0 kg object on Earth where gravitational field strength is 9.8 N/kg.

32.Complete the sentence: The gravitational field strength on Earth is approximately ___ N/kg.

33.State the equation that links weight, mass, and gravitational field strength.

34.A liquid has a density of 0.8 g/cm³. A solid object has a mass of 120 g and a volume of 100 cm³. When placed in the liquid, the object will:

35.A force meter (newton meter) is used to measure the weight of an object on Earth. The reading is 20 N. The object is then taken to a planet where gravitational field strength is half that of Earth. What will be the reading on the force meter?

36.A student uses a measuring cylinder to measure the volume of a stone by water displacement. The initial water level is 40 cm³. After adding the stone, the level is 55 cm³. The stone's mass is 45 g. What is its density?

37.A bottle contains 500 cm³ of cooking oil of density 0.9 g/cm³. What is the mass of the oil?

38.Which of the following correctly describes the relationship between mass and weight?

39.A block of wood floats in water with half its volume submerged. The density of water is 1.0 g/cm³. What is the density of the wood?

40.A student wants to determine the density of a liquid. She places an empty measuring cylinder on a digital balance and records the mass as 50 g. She then pours 100 cm³ of the liquid into the cylinder and records the new mass as 130 g. What is the density of the liquid?

41.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. What is the independent variable?

42.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Which observation or quantity is the dependent variable?

43.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Which decision best controls another factor in this comparison?

44.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Why should the class repeat measurements or check multiple comparable observations?

45.A class is evaluating an application of mass, weight, density and model limits. Which statement identifies a relevant limitation?

46.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Which conclusion is most justified by a controlled comparison?

47.Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Select the two practices that strengthen the validity of this comparison.

48.When evaluating evidence about mass, weight, density and model limits, select the two scientifically defensible statements.

49.Design a fair investigation for this question: Compare density estimates for safe irregular solid objects using mass measurements and displaced water volume. Identify what to compare, what to record and one control.

50.Explain one use of the science in mass, weight, density and model limits and evaluate one limitation of the evidence or application.

51.A solid has mass 270 g and displaces 100 cm3 of water. What is its density in SI units?

52.Air bubbles cling to a submerged solid during a displacement measurement. Its mass reading is unaffected. How can this bias its calculated density?