Recent content by cmkc109

Homework Statement 2. The attempt at a solution Is it only possible when 600J of heat is exhausted and 400J of heat is converted into work? Is the 600J heat will enter the cold reservoir and available to do work again? q1/T hot + q3 / T cold = 0 q3 = 600 when T = 300K

the ground of course..

Homework Statement A ball is thrown up , another is dropped. Do they arrive at the same time? Homework Equations The Attempt at a Solution I think they won't because the ball which is thrown up has a greater distance to travel, but I am not sure, can someone explain please?

i don't remember :/ but in general, how to solve this question?

Homework Statement A car travels at a speed v (km/h) for 40 minutes, then at a speed v/2 for 40 minutes, and finally at a speed v/3 for 20 minutes. What is the average speed for the trip Homework Equations avg v = displacement / time The Attempt at a Solution 40v + 20v + 20/3 v...

Homework Statement The diagram shows two pulses, each of length , traveling toward each other at equal speed in a rope Which diagram below best represent sthe shape ofthe rope when both pulses are in region AB? Homework Equations The Attempt at a Solution The answer is the...

looks right to me

I got the answer. 1 wave is 0.05 sec frequency is the the number of cycles per sec so here 1 cycle / 0.05 sec so 1 sec/ 0.05 = 20

ok thanks

Homework Statement How do you find wavelength given this wave graph? [ignore my title please]Homework Equations c= (wavelength)(frequency)The Attempt at a Solution I always see displacement (y) vs distance (x) graph, but this one is displacement (x) vs t I'm kinda confused how you solve...

Homework Statement Estimate the fundamental frequency of resonance sound induced by blowing on the open end of a half liter bottle Homework Equations f= 1c/4L The Attempt at a Solution i don't know the length of L, what's half liter bottle ..? What does it tell you? 2 x f1?

The center of mass only change if there is external force applied on the system. But here there is only a change in the balance, but the overall force is the same, so the CoM remains the same. From the calculation, you see we get an answer of 1.7m, but since the CoM remains the same, the system...

The first part is 1.488m For the second part, I got 1.711m 75 (3.2) + 80 (1.6) /215kg = 1.711 m The boat moves 1.711 - 1.488 = 0.223m I think I get it now, the center of mass of the boat won't change, so after they switch location, the boat actually moves to compensate that change. It will...

just wondering, does it mean the origin is still at x=0, but then now 75kg is acting at 3.2m, and 80kg at 1.6m ? So wouldn't the center of mass shift since the balance has changed?

i 've figured out! don't think i can delete the post..