# Thread: Anyone good with physics here?

1. ## Anyone good with physics here?

I really need help with my physics hw. We were given 70 problems to finish over spring break and out of the 70 i managed to finish only 20.

2. Perhaps you could explain what level is the physics? High school physics, if so what grade?

My cousin visits a math forum and they have a sub forum made for physics and other sciences, you should check it out:

http://cbb.sosmath.com/cgi-bin/UBB/u...ubb=forum;f=11

It should be relatively easy for them to solve the problem as their kind of math freaks!

3. well...im in 11th grade taking physics. however, i'm taking the advanced placement physics in our high school. it's just about the same as a college level physics class since we get college credit for passing the ap exam.

4. do your own homework. you will appreciate it 10 yrs later.

5. Originally posted by kwun
do your own homework. you will appreciate it 10 yrs later.
yea do your physics homework... you'd be suprised how useful it is later in life when you need to integrate the angular momentum of a non-linear object or need to estimate the speed of a horse that is perfectly round, and you'd be saying to youself, daaaayuuuum! i wish i paid more attention to this in highschool!

6. I think you guys are jumping to conclusion about the situation. Perhaps he was only able to do 20/70 questons because he didn't get the rest and therefore required assistance...

Yodums

7. yeah i would do my own physics hw if i understood the concepts...that's why i made this thread, to ask for simpler explanations since i cant understand any of the physics books i have. I have Physics B, w/o calculus...so there's no integration. If i understood the concepts i wouldnt need to ask for help, my weak points are mainly around electricity and heat. I'm very much confused with conductors, superconductors, capacitors, circuits, and any else that involve electricity and heat. Other than that, I'm pretty decent in physics.

So if there are any kind folks who wouldnt mind explaining the concept of a certain subject, not "DO MY HW" i would be very much grateful.

8. Originally posted by Joseph
So if there are any kind folks who wouldnt mind explaining the concept of a certain subject, not "DO MY HW" i would be very much grateful.
Isn't that what the teachers are there for?
tell you how I did it.
I looked at a book
I looked at another book and another, and another to look at the same problem from different explanations.

I came back to it another time and read those books again. I talked it over with a few people in the class.
Maybe talked it over with the tutor

Did a few other questions on the subject.

Eventually it sank in.

Of course, it doesn't mean that I was perfect, but I did manage to pull up my marks from 27% at the end of the 1st year A level physics to about 65% in the year. Oh yeah, it took time

9. well...i would ask my teacher but were on spring break. i would ask my friends but none of them are taking Advance Placement Physics, the ones that are taking physics are taking the high school physics and when i asked them, they had no clue. And my percentage in class is roughly an 87%. On my last test, i had the second highest score in our class. It was a 94%, the highest grade was a 96%. Yeah i do study, yeah i do my own homework, but there are times when i really need help cause i dont understand.

10. Originally posted by Cheung
Did a few other questions on the subject.

Eventually it sank in.
I remember when i had to do problem sets... way back in the day...

Cheung is definetly right on this one, especially for physics. Looking at how other people do it will not help you understand it... it'll only help you do the same type of problem later without fundamentally understanding why you did what you did.

Start doing questions that the books already gives answers and work your way up. You'll end up doing a lot of extra questions but you'll be awarded with newfound understanding that'll always be a fingertouch away.

For chemistry or biology though... i'd probably take the easy way though. There is no easy way in physics... you either learn it now or learn it later, and learning it later takes a lot longer.

11. Originally posted by bigredlemon
I remember when i had to do problem sets... way back in the day...

Cheung is definetly right on this one, especially for physics. Looking at how other people do it will not help you understand it... it'll only help you do the same type of problem later without fundamentally understanding why you did what you did.

Start doing questions that the books already gives answers and work your way up. You'll end up doing a lot of extra questions but you'll be awarded with newfound understanding that'll always be a fingertouch away.

For chemistry or biology though... i'd probably take the easy way though. There is no easy way in physics... you either learn it now or learn it later, and learning it later takes a lot longer.
A question keeps coming up in my mind, are you guys even paying attention to what i'm saying? I'm not asking for people to do my work for me. Since yesterday, I've been talking to a badminton forum member and has been helping me. Not giving me answers!!! Wanna see a pm i sent to that person yesterday regarding thermal physics? Try and see if im asking to give me the answers. I simply asked if i was doing it correctly. And if i have no clue as to where to start, i ask to point me in the right direction. I did the problem on my own.

seems right to me!

quote:
--------------------------------------------------------------------------------

Joseph wrote on 04-26-2003 03:02 AM:
Thanks!!!! That was really helpful, i managed to finish yet another problem. I think I have completed about 30/70 so far since this morning.

I have another topic i need help with. The topic is Heat and Temperature Change: Specific Heat Capacity.

Here's the given:

A piece of metal with a mass of 1.50 kilograms, specific heat of 200 J/kg C, and initial temperature of 100 C is dropped into an insulated jar thta contains liquid with a mass of 3.00 kilograms, specific heat of 1,000 J/kg C, and initial temperature of 0 C. The piece of metal is removed after 5 seconds, at which time its temperature is 20 C. Neglect any effects of heat transfer to the air or to the insulated jar.

okay, now this is what is going through my mind at this point:

t = 5 secs

For metal

m = 1.5 kg
c = 200 J/kg C
initial T = 100 C
final T = 20 C

For liquid

m = 3 kg
c = 1000 J/kg C
initial T = 0

The only equation that i can think of to use is Q=cm*deltaT

deltaT = change in temperature

The first question i am dealing with is asking to solve for the final temperature of the liquid.

I'm thinking that the heat, Q, is the same for both the metal and liquid. So I need to solve for Q.

Q = 1.5*200*(100-20)
Q = 24000 J

then solve for final T for the liquid.

24000 = 3*1000*(final T - 0)
24000 = 3000 T
T = 8 C

right?

For the second question its asking for the average rate at which heat is transferred while the piece of metal is in the liquid.

I just take the heat, Q, and divide it by the time the metal was in the liquid which was for 5 secs. So i should get 4,800 J/s right?

12. So you want us to confirm the answer you got?

Anyway the secret to high school physics is to carry all the units. If the units match up, it's near-impossible to get the answer wrong.

13. Well, i just want you guys to see if im doing everything right and if im completely stumped, steer me in the right direction. Like i had to do a problem consisting of time dilation. I had no idea i was dealing with a problem like that and was looking towards the doppler effect. I was completely stumped since i couldnt find f' or f, so i asked the person for help and told me to use time dilation. sorta like that kind of help. that was all i was asking for, nothing like do my homework or such.

14. Originally posted by Joseph
Well, i just want you guys to see if im doing everything right and if im completely stumped, steer me in the right direction. Like i had to do a problem consisting of time dilation. I had no idea i was dealing with a problem like that and was looking towards the doppler effect. I was completely stumped since i couldnt find f' or f, so i asked the person for help and told me to use time dilation. sorta like that kind of help. that was all i was asking for, nothing like do my homework or such.
If i could talk to myself today while i was in highschool... i'd say relax more. It's not going to matter if you got only 10 wrong instead of 30 wrong. In the grand scheme of things, it's very hard to mess up in a place like Cali. as long as you stay clear of drugs and such. There's usually a lot of pressure in asian families to do well, but you may find yourself to be unhappy in your life 10 years from now for spending so much of your prime youth indoors.

15. Yeah i guess, my parents expect me to have high grades. Ill get out more once summer comes around, but until then its...study, study, badminton...

16. Originally posted by bigredlemon
If i could talk to myself today while i was in highschool... i'd say relax more. It's not going to matter if you got only 10 wrong instead of 30 wrong. In the grand scheme of things, it's very hard to mess up in a place like Cali. as long as you stay clear of drugs and such. There's usually a lot of pressure in asian families to do well, but you may find yourself to be unhappy in your life 10 years from now for spending so much of your prime youth indoors.
For me I would say I should have spent more time thinking...thinking how to play more badminton

Later, you'll be saying, elementary physics SHC and dopplers

If I could get over 80% in my exams at high school, I would have been able to go to Oxford/Cambridge

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•