did you put in the units for its speed?KatieLynn said:Homework Statement
A 20 metric ton train moves toward the south at 50 m/s. What speed must it travel to have two times its original momentum?
Homework Equations
Change in momentum = mass(FinalVelocity - InitialVelocity)
The Attempt at a Solution
so I thought you would simply times 50 by 2 and get 100 to be the answer, but that's not right. First question is do you have to convert 20 metric tons to kilograms?
No, I meant 100m/s. In order for the momentum vector to be twice its original momentum, the new momentum must have a magnitude of twice as much and a direction in the same direction as the original momentum vector. Since its momentum doubles, and the mass is constant, then its velocity must double. So the velocity is 100m/s south. The speed is 100m/s. Unless we both missed something.KatieLynn said:you mean 50 m/s yeah?...if that's not what you mean then I'm confused
Momentum is a fundamental concept in physics that describes the quantity of motion of an object. It is a measure of how much an object is moving and in what direction.
Momentum is calculated by multiplying an object's mass by its velocity. The equation for momentum is p = m * v, where p is momentum, m is mass, and v is velocity.
The unit of measurement for momentum is kilogram meters per second (kg*m/s). This unit is derived from the units of mass (kilogram) and velocity (meters per second).
Momentum is closely related to Newton's laws of motion, specifically the law of inertia and the law of conservation of momentum. Newton's first law states that an object will maintain its state of motion unless acted upon by an external force. Momentum is the measure of an object's resistance to changes in its motion, so it is directly related to this law. The law of conservation of momentum states that the total momentum of a system will remain constant unless acted upon by an external force. This means that in a closed system, the total momentum before and after a collision will be the same.
There are many real-life examples of momentum, such as a car moving down the road, a ball being thrown, or a person riding a bike. In all of these cases, the objects have both mass and velocity, resulting in momentum. Another example is a train moving along the tracks, which has a large momentum due to its high mass and velocity. Additionally, a rocket launching into space also has a significant amount of momentum due to its high speed and mass.