Physics
posted by Jamie .
What is the spring constant of a spring that stores 25 J of elastic potential energy when compressed by 7.5 cm from its relaxed length?
I know that I should chnage 7.5 cm into .075 m. Is this equation correct? U(x)= 1/2kx^2. I should have gotten 89N/cm for the correct answer but it isn't working out.
U= 1/2 k x^2
k= 2U/x^2 = 2*25/.075^2=8900N/m^2 This does not convert to the answer you cited.
Or you can work it in cm..
U= 1/2 k x^2
2U/x^2 = 2*25/7.5^2 N/cm
Respond to this Question
Similar Questions

physics
a spring with spring constant k= 100N/m is at its equilibrium length a) how much elastic potential energy is stored in the spring? 
Physics
A spring with spring constant k=100 (N/m) is at its equilibrium length. a) How much elastic potential energy is stored in the spring? 
physics
A 4.9 g marble is fired vertically upward using a spring gun. The spring must be compressed 8.0 cm if the marble is to just reach a target 29 m above the marble's position on the compressed spring. (a) What is the change in the gravitational … 
Physics ( elestic potential energy)
A spring with a force of 5.2 N/m has a relaxed length of 2.45. When a mass is attached to the end of the spring and allowed to come to rest. the vertical length of the spring is 3.57m. Calculate the elastic potential energy stored … 
Physics
The length of a spring increases by 7.2 cm from its relaxed length when a mass of 1.4 kg is hanging in equilibrium from the spring. (a) What is the spring constant? 
Physics
A block with mass m = 2.00 kg is placed against a spring on a frictionless incline with angle θ=30.0° (see figure). The block is NOT attached to the spring. The spring, with spring constant k = 19.6 N/cm, is compressed 20.0 cm … 
Physics
What is the spring constant of a spring that stores 25 J of elastic potential energy when compressed by 6.0 cm from its relaxed length? 
physics
The staples inside a stapler are kept in place by a spring with a relaxed length of 0.115 m. If the spring constant is 51.0 N/m, how much elastic potential energy is stored in the spring when its length is 0.150 m? 
Physics
The staples inside a stapler are kept in place by a spring with a relaxed length of 0.115 m. If the spring constant is 51.0 N/m, how much elastic potential energy is stored in the spring when its length is 0.150 m? 
Physics
A spring with a force constant of 5.4 N/m has a relaxed length of 2.63 m. When a mass is attached to the end of the spring and allowed to come to rest, the vertical length of the spring is 3.64 m. Calculate the elastic potential energy …