Author Topic: physics  (Read 19306 times)

Offline ruby92

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Re: physics
« Reply #30 on: March 25, 2010, 09:20:26 pm »
why did u take the vertical component???

By the way Thanks a lot :D

Offline A.T

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Re: physics
« Reply #31 on: March 25, 2010, 09:27:33 pm »
c are u sure?
isnt it d??
from my concpets it IS C.

Offline A.T

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Re: physics
« Reply #32 on: March 25, 2010, 09:29:42 pm »
why did u take the vertical component???

By the way Thanks a lot :D

It depends if tension was in horizontal direction you would have to resolve horizontally,but now its vertical so we will have to resolve vertically and hence find the vertical component.

Offline ruby92

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Re: physics
« Reply #33 on: March 25, 2010, 09:32:29 pm »
ok so im gonna attempt figuring this out
thkxxx again

Offline ruby92

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Re: physics
« Reply #34 on: March 26, 2010, 05:19:52 pm »
Deformation of solids question:
in a force extension graph the area under the graph represents strain energy only upto the elastic limit?

Offline astarmathsandphysics

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Re: physics
« Reply #35 on: March 26, 2010, 05:30:42 pm »
Up to the breaking point

Offline halosh92

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Re: physics
« Reply #36 on: March 26, 2010, 08:16:33 pm »
could someone explain briefly which formulas do we use exactly for elastic and inelastic collisions
URGENT
thx
everyday we wake up is a miracle, then how do we say miracles dont happen?????

Offline A.T

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Re: physics
« Reply #37 on: March 26, 2010, 08:51:08 pm »
could someone explain briefly which formulas do we use exactly for elastic and inelastic collisions
URGENT
thx
For elastic:
m1u1+m2u2=m1v1+m2v2 OR you can use the energy conservation formula 

for inelastic
m1u1=m2u2=V(m1+m2)

Offline ruby92

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Re: physics
« Reply #38 on: March 26, 2010, 09:12:02 pm »
electricity question:
1.When a battery in a toy car delivers a current of 0.75A, the p.d across its terminals is 1.3 V. when the car's motion is reversed the current delivered by the battery and the p.d. across its terminals becomes 12A and o.80v respectively.
calculate for the battery
a)the emf
b)the internal resistance

2.physics oct nov 2005 q6 part A(explained in detail)
« Last Edit: March 26, 2010, 09:31:12 pm by ruby92 »

Offline astarmathsandphysics

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Re: physics
« Reply #39 on: March 26, 2010, 09:23:40 pm »
which paper is this from?

Offline ruby92

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Re: physics
« Reply #40 on: March 26, 2010, 09:26:51 pm »
the first question...it isnt from a worksheet the physics teacher gave us...

Offline astarmathsandphysics

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Re: physics
« Reply #41 on: March 26, 2010, 09:27:23 pm »
the last should be m1u1+m2u2=v(m1+m2)
for perfectly inelastic collsions - bodies stick together

Offline astarmathsandphysics

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Re: physics
« Reply #42 on: March 26, 2010, 09:29:09 pm »
I dont understand the question

Offline ruby92

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Re: physics
« Reply #43 on: March 26, 2010, 09:37:54 pm »
this is all thats given in the worksheet
there is no diagram or anything

ive attached the paper with the second problem.
its q6 part a

Offline A.T

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Re: physics
« Reply #44 on: March 26, 2010, 10:28:06 pm »
the first question...it isnt from a worksheet the physics teacher gave us...

LOL wut? :P

And for no oct/nov 2005 Q
Similarity is that they both have same wavelengths which is 3.
difference is phase difference the one is a sine wave the other is a cosine wave and they have a phase difference of pie(180 degree)(half wave)