Post your Physics questions here. (2 Viewers)

[_deloso]

HSC exams are coming.. need any help? ask them here and i'll try and answer it asap
option topic: Astrophysics

 

[josh_blick]

physics <3

 

[ohexploitable]

spaceships A and B are both going past each other at 0.9c

what is the velocity of spaceship B when observed from spaceship A???

 

[ohexploitable]

trollface.jpg

 

[_deloso]

spaceships A and B are both going past each other at 0.9c

what is the velocity of spaceship B when observed from spaceship B???

real question? and why would you ask me exploitable.. you're like king in your subjects. you don't need anyone's help dude

 

[RANK 1]

spaceships A and B are both going past each other at 0.9c

what is the velocity of spaceship B when observed from spaceship B???

velocity of spaceship b when observed from spaceship b is 0

 

[ohexploitable]

velocity of spaceship b when observed from spaceship b is 0

lol i meant from spaceship A

 

[Omnipotence]

Explain the concept of perpetual motion and outline an everday task that utilises this effect.

 

[powlmao]

Prove string theory.

 

[taeyang]

Solve:

P versus NP problem
Hodge conjecture
Poincaré conjecture
Riemann hypothesis
Yang–Mills existence and mass gap
Navier–Stokes existence and smoothness
Birch and Swinnerton-Dyer conjecture

In order.




Don't worry, there's a couple of rewards in there for you.

 

[_deloso]

*sigh please DON'T post your physics questions here

 

[RANK 1]

Explain the concept of perpetual motion and outline an everday task that utilises this effect.

perpetual motion is the concept that something can perform work indefinitely, there are no everyday tasks that utilises this effect as the concept violates the law regarding the conservation of energy

 

[hscishard]

spaceships A and B are both going past each other at 0.9c

what is the velocity of spaceship B when observed from spaceship A???

0.994c

 

[clementc]

Out of interest is this part of the HSC? I swear we only learn crap like time dilation, length contraction and "mass dilation" (which doesn't really occur), or is it possible to answer this question just using time+length dilation?
I know there's this formula for Einstein's relativistic addition of velocities based on the Lorentz transformations but I've never seen it in HSC before =\

 

[RANK 1]

yes you need to know all this

Solve:

P versus NP problem
Hodge conjecture
Poincaré conjecture
Riemann hypothesis
Yang–Mills existence and mass gap
Navier–Stokes existence and smoothness
Birch and Swinnerton-Dyer conjecture

 

[lusiv]

I have a preliminary question that i need help with...
Distance of 100km signal is 100 unit. What is the signal strength for 200km ?
thanks

 

[nightweaver066]

I have a preliminary question that i need help with...
Distance of 100km signal is 100 unit. What is the signal strength for 200km ?
thanks

Using the inverse square law, where Intensity is proportional to 1/distance^2,

since the distance has doubled, intensity is now proportional to 1/(2)^2 = 1/4

This means that the signal strength at 200km is 1/4 of the original signal strength which means it is 25 units.

 

[elbatiolpxeho]

I have a preliminary question that i need help with...
Distance of 100km signal is 100 unit. What is the signal strength for 200km ?
thanks

when I=100, d=100 so k=1000000



when d=200,

 

[lusiv]

How do you get k ?

 

[ohexploitable]

How do you get k ?

put I=100 and d=100 into teh equation