Matter

Based on the pictures, what is the mass of the flowerpot?

• less than 4 grams

• between 4 kg and 5 kg

• exactly 4.5 kg

• more than 5 kg

Answer explanation

Explanation: On a balance, the side with more mass will be lower. The first image shows that the flowerpot has less mass than the 5-kilogram mass. The second image shows that the flowerpot has more mass than four of the 1-kilogram masses. Therefore, the flowerpot's mass is between 4 and 5 kilograms. The exact mass of the flowerpot cannot be determined from these images.

What is the weight of the turkey?

• 15 newtons

• 52 newtons

• 71 newtons

• 202 newtons

Answer explanation

Explanation: To read a spring scale, see where the red pointer is lined up. The pointer on the scale is between 50 newtons and 75 newtons. It is closer to 75 newtons, so 71 newtons is the best guess.

The force of gravity on the surface of Mercury is much less than on Earth. A rock has a weight of 100 newtons on Earth. What do you know about the weight of the rock on Mercury?

• The rock will weigh exactly 100 newtons.

• The rock will weigh more than 100 newtons.

• The rock will weigh less than 100 newtons.

• There is not enough information to know if the rock weighs the same, more, or less on Mercury.

Answer explanation

Explanation: The weight of an object depends on its mass and the strength of gravity at that location. The stronger the force of gravity, the more the object will weigh. Gravity is much weaker on Mercury than on Earth, so all objects will weigh less on Mercury than on Earth.

A chair has a mass of 10 kilograms on Earth. What is the mass of the chair on Mercury?

• 10 kilograms

• more than 10 kilograms

• less than 10 kilograms

• not enough information

Answer explanation

Explanation: Mass is the amount of matter in an object. When an object is moved from Earth to Mercury, the amount of matter in the object does not change. The mass of an object remains the same in any location.

A watermelon is balanced by a dog, a pumpkin, a flowerpot, and a baseball as shown below. Which statement or statements are true?

• The mass of the watermelon is equal to the mass of the flowerpot, baseball, dog and pumpkin combined.

• The weight of the watermelon is equal to the weight of the flowerpot, baseball, dog and pumpkin combined.

• Both A and B are true.

• Neither A nor B is true.

Answer explanation

Explanation: For the balance to be balanced, the forces pulling down on each side must be equal. These forces are the weights of the objects. The weight of the watermelon must be equal to the total weight of the flowerpot, baseball, dog and pumpkin.

If two objects are in the same location and have the same weight, they also must have the same mass. The weight of an object can only change when the strength of gravity changes.

What is the volume of the liquid in the graduated cylinder below?

• 20.4 mL

• 24.0 mL

• 28 mL

• 30 mL

Answer explanation

Explanation: To read a graduated cylinder, first determine how much volume is represented by each tick mark. There are 10 tick marks from 20 mL to 40 mL, so each tick mark represents 2 mL. Next, read the volume from the bottom of the meniscus. The bottom of the meniscus is aligned with the tick mark representing 28 mL.

What volume is shown in the graduated cylinder?

• 10.4 mL

• 13.5 mL

• 14.0 mL

• 17.0 mL

Answer explanation

Explanation: On this graduated cylinder there are 5 tick marks from 10 mL to 15 mL, so each tick mark represents 1 mL. The bottom of the meniscus is halfway between the tick marks representing 13 and 14 mL, so the best estimate of the volume is 13.5 mL.

A graduated cylinder contains 20.0 mL of water. After a rock is placed in the cylinder, the level rises as shown below. What is the volume of the rock?

• 14 cm³

• 22 cm³

• 34 cm³

• 38 cm³

Answer explanation

Explanation: The total volume (rock plus water) in the graduated cylinder is 34 mL. We know the volume of water in the cylinder was 20 mL. Therefore, the volume of the rock must be 14 mL. Because a milliliter is exactly the same volume as a cubic centimeter, the volume of the rock is 14 cm3.