1. If the net force on an object is O N, the forces are considered unbalanced.

true
false**

2. Most people in the United States use feet and miles to measure distance in their everyday lives. Why do scientists in the United States use meters to measure distance?

Meters allow scientists t be more accurate in their measurments.**

Science requires special measurements that are not used in everyday life.

All scientists use meters to measure distance to help eleminate confusion.

Meters are better than feet for measuring objects in motion.

3. Which of the following forces causes a feather to fall slower than a bowling ball?

gravity

rolling friction

sliding friction

air resistance**

4. A small fish in the Pacific Ocean watches a shark swim by a large rock a few meters away. Which of the following is the reference point in this scenario?

shark**

large rock

water

Pacific Ocean

5. Which of the following pairs of objects would have the strongest gravitational pull?

two tall buildings in the same city

two tall buildings in different cities

two stars very far away from each other

two stars very close to each other**

6. A maglev train uses powerful magnets to lift the train above the track as it moves forward. Such a design reduces which of the following forces?

rolling friction**

gravity

air resistance

fluid friction

7. Which of the following examples does not demonstrate a change in velocity?

An elevator slows down in order to stop at the top floor.

A cruise shop travels west at a constant speed**

A soccer ball is passed across the field

A train remains at a constant speed as it moves around a bend.

8. Which of the follwing does not need to be measured in order to describe motion.

size of the object**

distance the object traveled

velocity of the object

acceleration of the object

Check, thanks

To answer these questions, here's how you can arrive at the correct answers:

1. To determine if the net force on an object is zero or not, you need to calculate the vector sum of all the forces acting on the object. If the net force is zero, the forces are considered balanced; if it is not zero, the forces are unbalanced. The correct answer is "false."

2. Scientists in the United States use meters to measure distance because the metric system, which includes the meter, is a universal system used in scientific research worldwide. It allows for consistent and accurate measurements across different fields of study. The correct answer is that meters allow scientists to be more accurate in their measurements.

3. When a feather and a bowling ball fall, the force of gravity acts on both objects. However, the feather experiences much more air resistance compared to the bowling ball due to its larger surface area. This air resistance counteracts the force of gravity, causing the feather to fall slower. Therefore, the correct answer is air resistance.

4. The reference point is the object or location that is used to describe the motion or position of other objects. In this scenario, the small fish is observing the motion of the shark in relation to the large rock. Therefore, the reference point is the shark.

5. The strength of the gravitational pull between two objects depends on their masses and the distance between them. According to Newton's law of universal gravitation, the force of gravity is stronger when the masses of the objects are larger and when the distance between them is smaller. Based on this, the correct answer is two stars very close to each other.

6. A maglev train uses powerful magnets to levitate above the track, which greatly reduces the force of rolling friction. Rolling friction occurs when objects are in direct contact with each other and can impede motion. By eliminating this friction, the maglev train can move more efficiently. Therefore, the correct answer is rolling friction.

7. A change in velocity refers to a change in speed or direction. In this case, the cruise ship traveling west at a constant speed does not demonstrate a change in velocity, as the direction remains constant. Therefore, the correct answer is a cruise ship traveling west at a constant speed.

8. To describe motion, you need to measure variables such as distance, velocity, and acceleration. However, the size of the object itself does not need to be measured to describe its motion. Therefore, the correct answer is the size of the object.

I hope this helps!

1. If the net force on an object is O N, the forces are considered unbalanced.

false

2. Most people in the United States use feet and miles to measure distance in their everyday lives. Why do scientists in the United States use meters to measure distance?

Meters allow scientists to be more accurate in their measurements.

3. Which of the following forces causes a feather to fall slower than a bowling ball?

air resistance

4. A small fish in the Pacific Ocean watches a shark swim by a large rock a few meters away. Which of the following is the reference point in this scenario?

shark

5. Which of the following pairs of objects would have the strongest gravitational pull?

two stars very close to each other

6. A maglev train uses powerful magnets to lift the train above the track as it moves forward. Such a design reduces which of the following forces?

rolling friction

7. Which of the following examples does not demonstrate a change in velocity?

A cruise ship travels west at a constant speed.

8. Which of the following does not need to be measured in order to describe motion?

size of the object

Check, thanks