Energy
Who would ever know that energy is part of physics? By definition, energy is defined as "a thing". There are three types of energies: kinetic(k), gravitational (ug), and elastic potential (us). Kinetic is dealt with movement and velocity. Gravitational is dealt with height or position of the object. Elastic potential is dealt with spring compression. This system is measured in Joules.(j)
Units used:
K= kintetic
v= velocity
m=mass
h=height
g=9.8
k(Us)= constant
x= position
Units used:
K= kintetic
v= velocity
m=mass
h=height
g=9.8
k(Us)= constant
x= position
I will be demonstrating
NRG 1 - I can use words, diagrams and bar graphs to analyze energy stores and energy transfers for a system
NRG 2 - I can calculate the system's kinetic energy, gravitational potential energy, and elastic potential energy
NRG 3 - I can apply energy conservation to solve problems
NRG 4 - I know how the direction of force and displacement affect the mechanical energy transfer into/out of a system
NRG 5 - I can use mechanical energy transfer to solve problems
NRG 6 - I can determine the rate of energy transfer into/ out of within a system.
NRG 1 - I can use words, diagrams and bar graphs to analyze energy stores and energy transfers for a system
NRG 2 - I can calculate the system's kinetic energy, gravitational potential energy, and elastic potential energy
NRG 3 - I can apply energy conservation to solve problems
NRG 4 - I know how the direction of force and displacement affect the mechanical energy transfer into/out of a system
NRG 5 - I can use mechanical energy transfer to solve problems
NRG 6 - I can determine the rate of energy transfer into/ out of within a system.
Question
A cart moving at 5m/s collides with a spring at the instant the cart is motionless, what is the largest amount that the spring will be compressed? With no friction.
A) define the system energy flows then complete energy bar graphs
B) construct quantitative conservation equation
c) determine the max compression
A) define the system energy flows then complete energy bar graphs
B) construct quantitative conservation equation
c) determine the max compression
ExplanationsPosition A: The cart originally is traveling to the right. Because it is on the ground. Ug is equal to 0 because it's at ground height. Since there is no spring, Us is 0 as well. Therefore, all the energy is present in kinetic. The force is going to move tot he right until it hits the spring.
System flow: All the kinetic energy goes transfers to Us because of the conservation of energy says all the energy stays in the system. K transfers to Us becuase Ug is not present. K is not present in Position B because there is no velocity/motion. However, there is a spring so all energy goes into it. (4 bars) Position B: Due to law conservation of energy, all the energy stays in the system. All the four energy bars transfers the energy that was traveling to the right has now compressed into a spring. Force Diagram: Because the cart is moving at a constant velocity. There are no forces pushing it other than normal and weight force which are balanced. Quantitative Conservation Equation: As shown all the energy stays in the system in postion a and postiion B. The final Points in energy are 100 joules. Max Compression: Given that K=50N/m, Plug it into the elastic potential equation which turns out to be. Us = 1/2(k)(x^2) and solve for x. and you should receive an answer of 2 meters. |