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nineteen

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In summary, the conversation discusses why kinetic energy is a scalar quantity and provides examples to understand this concept. It is mentioned that energy in general is a scalar quantity and the inner product of any two vectors is also a scalar quantity. The reference article states that momentum, which is proportional to velocity, is a vector quantity and the direction of motion makes a difference in collisions. It is also explained that energy is proportional to the square of velocity and it takes the same amount of energy regardless of the direction of motion.

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nineteen

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This is not an appropriate reference. In order to know what you read we need to know which article. Please provide a reference.nineteen said:I read in an article

The inner product of any two vectors is a scalar quantity. So in particular, the inner product of a vector with itself, i.e., the square of the vector, is a scalar quantity.

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anorlunda

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Momentum, which is proportional to velocity, is a vector quantity. When two cars collide, it makes all the difference in the world if they were traveling in the same direction or in opposite directions.

Energy is proportional to the square of velocity. It takes the same energy (fuel burned) to accelerate a car from a stop to cruising speed, or to travel 100 km, regardless of whether the car is heading north, south, east or west.

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nineteen

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Orodruin said:Energy in general is a scalar quantity. It is how it is defined, whether kinetic or potential.This is not an appropriate reference. In order to know what you read we need to know which article. Please provide a reference.

The inner product of any two vectors is a scalar quantity. So in particular, the inner product of a vector with itself, i.e., the square of the vector, is a scalar quantity.

Thank you very much. I think I got what you taught. https://van.physics.illinois.edu/QA/listing.php?id=347&t=momentum-and-kinetic-energy This is the reference for that page I was talking about in the thread I started. This is kind of a Q and A article.

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nineteen

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anorlunda said:

Momentum, which is proportional to velocity, is a vector quantity. When two cars collide, it makes all the difference in the world if they were traveling in the same direction or in opposite directions.

Energy is proportional to the square of velocity. It takes the same energy (fuel burned) to accelerate a car from a stop to cruising speed, or to travel 100 km, regardless of whether the car is heading north, south, east or west.

Explained so simply. Thank you very much friend.

Kinetic energy is the energy an object possesses due to its motion. It is a scalar quantity, meaning it only has magnitude and no direction.

Kinetic energy is considered a scalar quantity because it only has magnitude and no direction. This is in contrast to vector quantities, which have both magnitude and direction.

Kinetic energy is different from other forms of energy because it is specifically related to an object's motion. Other forms of energy, such as potential energy, are related to an object's position or state.

Yes, kinetic energy can be negative. This occurs when an object is slowing down or moving in the opposite direction of its initial motion. In this case, the kinetic energy is considered to be negative because it is doing work against the direction of its motion.

Kinetic energy is calculated using the formula KE = 1/2 * m * v^2, where m is the mass of the object and v is its velocity. This formula takes into account both the mass and velocity of the object, as they both contribute to the amount of kinetic energy an object possesses.

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