Are you sure this is an accurate statement of the problem? There doesn't seem to be enough information to find the spring constant. (The same conditions can apply to any spring constant.)alfredo24pr said:A "mass less" spring has a length of 0.350 m in its relaxed position. It is compressed to 70.0 percent of its relaxed length, and a mass M= 0.150 kg is placed on top and released from rest. Find the spring constant
Doc Al said:Are you sure this is an accurate statement of the problem? There doesn't seem to be enough information to find the spring constant. (The same conditions can apply to any spring constant.)
Make sure you've presented the problem exactly as given to you, word for word.
You haven't made use of the 1.5 second time. That should give you a clue where you might have missed something.alfredo24pr said:Am I doing something wrong?
Doc Al said:You haven't made use of the 1.5 second time. That should give you a clue where you might have missed something.
Also: Your use of mgh=1/2kx^2 ignores the kinetic energy that the mass has once the spring uncompresses.
Sounds good. Use the time to figure out the speed.alfredo24pr said:Oh, so I was thinking:
mgh + 1/2mv(sqrd) = 1/2kx(sqrd)
Is that correct?
Doc Al said:Sounds good. Use the time to figure out the speed.
Doc Al said:Sounds good. Use the time to figure out the speed.
How did you figure out the speed? (Hint: Once the mass leaves the spring, it's a projectile.)alfredo24pr said:Im not getting the answer
1/2kx2 = mgh + 1/2mv2
1/2k (0.245)2 = (.150)(9.8)(0.105) + 1/2 (0.150)[(0.245/1.5)]2
Doc Al said:How did you figure out the speed? (Hint: Once the mass leaves the spring, it's a projectile.)
Not exactly:alfredo24pr said:So, every other thing is correct? it is just the speed?
alfredo24pr said:1/2k (0.245)2 = (.150)(9.8)(0.105) + 1/2 (0.150)[(0.245/1.5)]2
You don't have the distance. But you can directly relate speed and time.I have to use: y = yo + voyt - 1/2gt2?
Doc Al said:Not exactly:
How did you get that displacement?
You don't have the distance. But you can directly relate speed and time.
No. How much is the spring compressed? (You had this figured out in your first post.)alfredo24pr said:ok.. so,
1/2kx2 = 1/2k (0.350)2 right?
You don't need displacement. How are velocity, acceleration, and time related?I really do not understand how to get the speed. Obviously the time is 1.5s, but what displacement do I use?
Doc Al said:No. How much is the spring compressed? (You had this figured out in your first post.)
You don't need displacement. How are velocity, acceleration, and time related?
The spring constant is a measure of the stiffness of a spring and is defined as the force required to stretch or compress a spring by a unit length.
A mass-less spring is a theoretical concept where the spring does not have any mass, and its weight can be ignored when calculating its behavior. In reality, all springs have some mass, but for simplicity, the mass is often neglected in theoretical calculations.
The spring constant of a mass-less spring can be determined by measuring the force required to stretch or compress the spring by a certain distance. The spring constant is equal to the ratio of the applied force to the displacement.
No, the spring constant of a mass-less spring can vary depending on the material and shape of the spring. It can also change if the spring is stretched beyond its elastic limit, which can cause permanent deformation.
The spring constant determines the strength of the force exerted by the spring when it is stretched or compressed. A higher spring constant means a stiffer spring that requires more force to stretch or compress, while a lower spring constant means a weaker spring that requires less force.