# Recent content by vu10758

1. ### Our class has only completed ~50% of the Physics B Curriculum

I didn't take AP Physics so I wouldn't know but I am taking an introductory physics class right now. I am not sure how hard AP Physics is but that sounds like a lot of materials. I would say optics is probably the easiest topic at least as far as math in concern. The formulas (at least in my...
2. ### Work done in an Isobaric expansion

I am sorry I can't really follow the work. Please include the units. I would approach this problem this way... First of all, I would sketch a P-V diagram. It starts at some pressure and volume and then undergoes an isobaric expansion tripling its side. With p on your vertical axis and v on...
3. ### Glasses to fix near points and far points

If -2.62 is 1/f and the answer is indeed .34 for as in the answer key then o must be greater than 3 meters away. How is that possible? Do I somehow combine that 1.98 m with the other part a, which is .82 meters?
4. ### Finding length and longitudinal magnification

Homework Statement A small object of length dL is placed on the axis of a converging mirror of focal length f. The center of the object is a distance o from the mirror. Determine the length of the image and thus effective determine a longitudinal m' = dL'/dL for the lens. Homework...
5. ### Glasses to fix near points and far points

Thanks for your help. I just realized that I need help for part b as well. b) 1/f = 1/o + 1/i The person's far point is .6 or .58 from the glasses. I want him to see at .25 m or .23 m from the glasses. 1/-f = 1/.58 + 1/-.23 1/-f = -2.62 1/f = 2.62 that is the power. I am...
6. ### Glasses to fix near points and far points

Homework Statement a)A person has a near point of .6m and far point of 2m . What power of glasses would be needed for the person to see infinitely far away. Assume that glasses are 2cm from the person's eyes. If the person used those glasses, what would his new near point be? b) What...
7. ### Mixing ice, steam, and water and find equilibrium

Thank you very much for the help
8. ### Mixing ice, steam, and water and find equilibrium

Homework Statement .15 kg of steam at 100 degree Celcius is mixed with .2kg of water at 50 degree and .2 kg of ice at 0 degree. Determine the final temperature and phase(s) of the final state. Assume that no energy is lost to the surroundings. Homework Equations The Attempt at a...
9. ### Roof withstanding a storm

Homework Statement Someone is putting a small shed in their backyard. The roof is not nailed down so gravity alone is holding it down. The wind suddenly flows across the top of the roogf at 20 m/s. The air inside the shed is 1.01 x 10^15 Pa, the normal atmospheric pressure. The roof has an...
10. ### Density and simple harmonic motion

Never mind I got it now. Thanks a lot for your help.
11. ### Density and simple harmonic motion

For the object at rest I got B - mg = 0 When it's pushed down B - mg -f = -ma Since B =mg f = ma I already know this though so how does it help prove that it's in simple harmonic motion with a repeating pattern?
12. ### Density and simple harmonic motion

When the object is at rest, I have mg pulling down and buoyant force pushing up. They are equal in magnitude. The net torque is also zero. When the object is pushed down I have f pushing down, mg pulling down, and buoyant force pushing up. This extra f is enough to push it down. My net...
13. ### Density and simple harmonic motion

Homework Statement A mass of density d floats in a liquid of density d_L. The mass is then pushed down a distance x and let go. Use Newton's Second Law to demonstrate that the mass will undergo simple harmonic motion. Recall that the SHM equation is d^2x/dt^2 + w^2*x = 0. Assume there is...
14. ### Releasing a sphere from water

Thanks. I will try it again.
15. ### Releasing a sphere from water

Homework Statement A 1kg hollow sphere of volume .00419m^3 is released from rest at the bottom of a 2m deep pool of water (density of water is 1000kg/m^3). The sphere accelerates upwards and flies out of the pool. How high does it get above the pool before coming down. Ignore the brief time...