Physics MCQs thread.

[hassam]

no i was asking proof for.....time thing that zishi said

 

[xHazeMx]

D

 

[Zishi]

please solve this one..

A. The main mistake which candidates do is that they assume initial velocity to be zero. Let it be u, make two equations. solve them simultaneously, and you'll get the answer.

i know.. i kept "u'' as initial velocity, but still couldnt get the right answer.
could u please tell me the equations ??

Here you go:

In the 4th line, it's "2nd equation" instead of first one.

 

[Zishi]

u give me a rigorous proof then

I think you're talking about motion with no air resistance, for that both times are same. But with air resistance they ain't same.

 

[Hateexams93]

WHHY ITS A???how is I1 >I2 ?

 

[Zishi]

C, I guess. It may be wrong, thinking on it...

 

[Hateexams93]

C, I guess. It may be wrong, thinking on it...

is it A ?

 

[hassam]

C !!!

 

[Zishi]

C !!!

Glad to know that I was right. 8)

 

[xHazeMx]

C !!!

gravity is always constant . how did i forget that -_-

 

[hassam]

 

[Hateexams93]

and can some1 plz answer to my question ?on previous page

 

[hassam]

 

[Hateexams93]

C !!!

utwhat about directions ? when its bouncin back , isn't it accelerating in opposite direction ?

 

[girlscampisra]

thanks a lot Zishi and Unique!!

 

[xHazeMx]

C and D right ?

 

[kakarocks]

I HATE STATIONARY WAVES!

 

[Arshiful]

WHHY ITS A???how is I1 >I2 ?

Imagine

pipes and water

when the diameter of the pipes are small the ease of flow of water is less
whereas when the diameter of the pipes are bigger the ease of flow of water is much more

so when the value of resistor is high it means that the flow of current is reduced
and when value of resistor is small more current can flow

so, current through 3 ohm resistor is less than 2 ohm
I1<I2

now find the combined resistance of 3and6 ohm and 2and2 ohm resistors individually

comb resistance of 3and6=(3*6)/(3+6)=2-------------------(1)
comb resistance of 2and2=(2*2)/(2+2)=1-------------------(2)

as we know PD is proportional to R(1)>R(2)

so V1>V2 therefore answer C

 

[girlscampisra]

A is the answer for this hassam .. antinodes are formed at the open end!

 

[kakarocks]

WHHY ITS A???how is I1 >I2 ?

IT's C as the others said . Current is divided equally in the Second one . And as you know Greater Resistance = Greater p.d