Recent content by Kalix

Sorry the picture got a little messed up on the computer. Hopefully it will be easy to tell where things go based on the other information.

Homework Statement Question: Two strings at different lengths and linear densities are joined together. They are stretched so that the tension in each string is 190.0 N. The free ends are fixed in place. Find the lowest frequency that permits standing waves in both strings with a node at the...

Homework Statement Question: Two trains on separate tracks move toward one another. Train #1 has a speed of 130 km/hr and train #2 a speed of 90km/hr. Train 2 blows its horn, emitting a frequency of 500 Hz. What frequency is heard by the engineer on train #1? Homework Equations This is...

So does that mean that the sun is transferring heat in the form of radiation? Is there an exact definition or are examples the best way to describe it?

Homework Statement Radiation is a type of heat transfer but I don't understand how it works. I know that conduction is direct contact and convection uses mass transfer to move heat but what does radiation do. My teacher never gave clear examples so some examples of how applies to heat transfer...

So when I use the conservation of ME equation I am solving for the final height correct? But what equation do I use to find the energy left over. If I have KE what do I subtract from that to see what is left?

We did a similar problem to this in class and KE was equal to PE so I thought it might be the same case. So this means that the height I found in parts a and b wasn't correct because I used KE as the PE value in the equation PE=mgh?

Yes we can assume that the initial speed is zero when the package is dropped from the plane. I actually don't know how to find total energy. I don't see the equation on the equation sheet that my teacher gave us. It seems likely that TE might equal KE + PE but I really don't know for sure. Also...

Homework Statement Question: An airplane is 250m from the zero heigh and drops a package: a. What is the objects kinetic energy if the velocity is moving at 10m/s. How much energy is left? What height should the object be at? b. What is the objects kinetic energy if the velocity is...

So what equation do I use for b. if I use FΔt=mVf-mVi I get the same answer as I do in a. I thought about using F=ma but I don't have the acceleration.

Okay so for impulse I think it is FΔt=ΔmV So I get the same answer for both a and b?

In my book it says the definition of impulse is "the product of the force and the time over which the force acts on an object" The wording is what really confuses me. What does "the product of the force mean"? Newton's third law?

oh I thought I was doing part a. Then how do you find impulse? Is there another equation for that? The for part c how is that any different than part b. Is it just the opposite. So 205333. (not negative) and finally for part d I understand how to find acceleration (F=ma i think) but how do I...

Homework Statement Question:A 2,800kg car is traveling at a velocity of 22m/s. The car hits the wall and comes to a complete stop. The collision took 0.3 seconds. a. What is the cars impulse? b. What force did the wall exert on the car? c. What force did the car exert on the wall? d...

I understand that I have the correct equations but I don't know how to solve them? As I said I have great difficulty in isolating variables so I guess that is what I am asking.