1. True or False: If the net force of an object is 0 N, the forces are considered unbalanced.
A.)True
B.)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.
Science requires special measurements that are not used in everyday life.
All scientists use meters to measure distance to help eliminate 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 reference point in this scenario?
A.)shark
B.)large rock
C.)water
D.)Pacific Ocean**
5. Which of the following pairs of objects would have the strongest gravitational pull?
two 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 tracks as it moves forward. Such as 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 ship 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 the bend
8. Which of the following does not need to be measured in order to describe motion?
size of an object
distance the object traveled
velocity of the object**
acceleration of the object
Please tell me if these are correct, thank you.
4. Rethink. How is the fish keeping track of where the shark is going?
5,7,8 rethink
4.)B
5.)D
7.)B
8.)D?
can yall tell me if Voldemort is correct asap
1. False. If the net force of an object is 0 N, the forces are considered balanced, not unbalanced. To determine if the forces are balanced or unbalanced, you need to find the vector sum of all the forces acting on the object. If the net force is zero, the forces are balanced; if it is not zero, the forces are unbalanced.
2. All scientists use meters to measure distance to help eliminate confusion. This is the correct statement. Scientists use the metric system, which includes the meter, because it provides a standardized system of measurement that is used worldwide. This allows for consistency and ease of communication between scientists from different countries.
3. Air resistance. This is the correct answer. When a feather falls, it experiences more air resistance compared to a bowling ball due to its larger surface area and shape. This air resistance slows down the feather's descent, causing it to fall slower than the bowling ball, which experiences less air resistance.
4. D) Pacific Ocean. This is the correct answer. In this scenario, the reference point is the Pacific Ocean because it is the fixed point in the environment that the fish is observing the motion of the shark and the large rock relative to.
5. Two stars very close to each other. This is the correct answer. The gravitational pull between two objects depends on their masses and the distance between them. In this case, two stars very close to each other would have the strongest gravitational pull because their masses are typically much larger than the mass of buildings and their proximity amplifies the gravitational force.
6. Rolling friction. This is the correct answer. A maglev train uses magnetic levitation to lift the train above the tracks, reducing the contact area between the train and the tracks. This reduces rolling friction, which is the resistance encountered by a rolling object on a surface.
7. A soccer ball is passed across the field. This is the correct answer. A change in velocity means a change in speed or direction. In this case, passing a soccer ball across the field does not involve a change in velocity as the ball continues to move with a constant speed and direction.
8. Velocity of the object. This is the correct answer. Velocity is a vector quantity that describes both speed and direction. To fully describe motion, you need to measure an object's displacement or distance traveled, the time it takes to travel that distance, and any changes in speed or direction (acceleration). The velocity itself is a result of these measurements, so it does not need to be measured directly.