# Worksheet: Measuring Masses

In this worksheet, we will practice identifying correct and incorrect uses of digital weighing scales for measuring the masses of liquids and solids.

Q1:

Which of the following instruments is used to measure an object’s mass?

• AA Geiger counter
• BA light gate
• CA weighing scale
• DA thermometer
• EAn ohmmeter

Q2:

Timmy uses a Newton meter to measure the weight of a brick. He gets a value of 14.7 N. How can he find the mass of the brick from this value?

• ABy squaring the value
• BBy dividing the value by the local gravitational field strength
• CBy square-rooting the value
• DBy multiplying the value by the local gravitational field strength
• EBy subtracting the value from the local gravitational field strength

Q3:

Which of the following can be used to directly measure an object’s weight?

• AA light gate
• BA micrometer
• CA Geiger counter
• DA barometer
• EA Newton meter

Q4:

Michael uses a digital weighing scale to measure the mass of a plank of wood, as shown in the diagram. He determines that the mass of the plank of wood is 2.912 kg. Which of the following statements explains why this value is incorrect?

• AOne end of the plank is resting on the table beside the scale, supporting some of the object’s weight. All of the weight must be supported by the weighing scale in order for the scale to measure the mass of the object.
• BThe value should be rounded to 3 significant figures.
• CThe plank of wood is resting on one side of the weighing scale. The wood must make contact with the center of the scale for the scale to measure the mass of the wood properly.
• DMichael forgot to zero the scale before taking the measurement.

Q5:

David uses a digital weighing scale to measure the mass of a steel cube. He zeroes the scale, places the cube on the scale, and pushes down on it, as shown in the diagram. He determines that the mass of the cube is 1.560 kg. Which of the following statements explains why this answer is incorrect?

• AThe scale was not zeroed before the steel cube was placed on it. The actual mass of the cube is greater than 1.560 kg.
• BAs he is pushing down on the block, the downward force on the scale is greater; therefore, the scale is going to measure the mass as being lower than it actually is.
• CAs he is pushing down on the block, the downward force on the scale is greater; therefore, the scale is going to measure the mass as being higher than it actually is.
• DThe scale was not zeroed before the steel cube was placed on it. The actual mass of the cube is less than 1.560 kg.

Q6:

Daniel uses a digital weighing scale to measure the mass of a cube of aluminum. He zeroes the scale, and then holds the cube on the scale, supporting some of its weight with his hand. He determines that the mass of the cube is 0.016 kg. Which of the following statements explains why this answer is incorrect?

• AThe scale was not zeroed before the aluminum cube was placed on it. The actual mass of the cube is less than 0.016 kg.
• BThe scale was not zeroed before the aluminum cube was placed on it. The actual mass of the cube is greater than 0.016 kg.
• CBy holding the block and supporting some of its weight, he is reducing the total downward force on the scale. This is increasing the value of the mass that the scale gives.
• DBy holding the block and supporting some of its weight, he is reducing the total downward force on the scale. This is lowering the value of the mass that the scale gives.

Q7:

Sophia uses a digital weighing scale to measure the mass of a metal cube. The left-hand side of the diagram shows the reading of the scale before she places the metal cube on it, and the right-hand side shows the reading after she places it. Sophia determines that the cube has a mass of 0.35 kg. Which of the following statements explains why this answer is incorrect?

• AThe scale was not zeroed before the metal cube was placed on it. The actual mass of the cube is greater than 0.35 kg.
• BThe metal cube was placed on one side of the weighing scale, rather than in the center. This means that the recorded mass is less than the actual mass.
• CThe metal cube was placed on one side of the weighing scale, rather than in the center. This means that the recorded mass is greater than the actual mass.
• DThe scale was not zeroed before the metal cube was placed on it. The actual mass of the cube is less than 0.35 kg.

Q8:

Elizabeth uses a digital weighing scale to measure the total mass of two metal cubes. Both cubes are made of nickel, but one cube is much larger than the other. She measures the mass of the larger cube first, as shown on the left-hand side of the diagram. Then she measures the mass of the smaller cube, as shown on the right-hand side of the diagram. She determines that the total mass of the two cubes is 23.520 kg. Which of the following statements explains why this answer is incorrect?

• AThe digital weighing scales are giving a reading in kilograms for the larger cube and grams for the smaller cube. Elizabeth has not converted the units of the second measurement before adding the two values.
• BElizabeth has forgotten to zero the scale before the second mass measurement.
• CSince the second mass measurement is only given to 2 decimal places, the total mass measurement should also be given to 2 decimal places, which is 23.52 kg.
• DSince the first mass measurement is only given to 3 significant figures, the total mass measurement should also be given to 3 significant figures, which is 23.5 kg.

Q9:

Noah uses a beaker and some digital weighing scales to measure the mass of some water. He zeroes the scales, places the beaker on the scales, and then pours the water into the beaker, as shown in the diagram. He determines that the mass of the water is 0.860 kg. Which of the following statements explains why this answer is incorrect?

• AThe beaker was placed on one side of the weighing scale rather than the center. This means that the recorded mass is greater than the actual mass.
• BThe beaker was placed on one side of the weighing scale rather than the center. This means that the recorded mass is less than the actual mass.
• CThe weighing scales need to be zeroed after the beaker is put on them but before the water is poured in; otherwise, the weighing scales measure the mass of both the water and the beaker.

Q10:

David uses two digital weighing scales to measure the masses of two metal cubes, as shown in the diagram. The metal cubes have different sizes and are made of different materials. He determines that the total mass of the two cubes is 1.041 kg. Which of the following statements explains why this answer is incorrect?

• AThe two scales are using different units. David must convert one of the mass measurements to the unit of the other before adding them to find the total.
• BThe masses are not positioned in the center of the weighing scales; therefore, the readings are inaccurate.
• CThe masses are not positioned in the same part of the weighing scales; therefore, the readings are inaccurate.
• DSince the two measurements individually are given to 3 significant figures, the value of the total mass should also be given to 3 significant figures, which is 1.04 kg.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.