Lab 1; PROBLEM #1: SPRINGS AND EQUILIBRIUMI
The relationship between, extension length of a spring, mass, tension and force was able to be determined by the usage of different mass objects, a spring and a cart. Different masses of an object was used to clearly show the relationship mentioned above. The relationships seem to return to formulas. This being; T = m (g + a) and F=-kx.
A biophysics research group is studying the mechanics of DNA during cell division. One of the more common methods these researchers involves the usage of tweezers, to find out the force needed to straighten the DNA molecule from its normal coiled shape. By experimenting on the relationship between the string’s DNA stretching length and the bead’s mass, the researchers will be able to determine how much bead’s mass affects the DNA’s response to the pulling force. To set up these two models were made. In the first model, a mass of an object was directly attached to a spring. The object mass could be changed. In the second model, an object mass was running over a pulley and is attached to a cart. One end of the spring is attached to the cart and the other end to an end-stop fixed to the track. The mass of the object and the cart’s weight was changeable.
First we calculate the Force.
Then find out the springs constant.
Springs constant = K = Newton divided by meters
After this we find the length the spring stretch
You can find the tension
T = m (g + a)
Final equation we come into was
0=ma + kx
Ma= -Kx which is can be said as F=-kx
We predicted that for every 5g, length of spring is .7cm longer. We also thought that all of the graphs will appear linear. Hence as the mass increase so does the tension of the spring and the force.
1st model: we first measure the unextend length of the spring. Then we measured the length of the spring after attaching an object of a certain mass. This can be seen in Figure 1.