Biology; Chemistry; Physics: Post your doubts here!

[farhan141]

Anyone please explain me.. Answer will be appreciated.

View attachment 27403

Answer is D right?

 

[Mustafa Malik]

ok so can u ppl tell how high n how low can the threshold be for the science subjects?

 

[bubbles1997]

Anyone please explain me.. Answer will be appreciated.

View attachment 27403

D

 

[bubbles1997]

Yeah, they've asked us what affects do AMPLITUDE and FREQUENCY have on loudness and pitch.

ok ok.. I get it..

 

[papajohn]

D

The ans is C. Donno why acceleration decreases

 

[TheStallion-Reborn]

Anyone please explain me.. Answer will be appreciated.

View attachment 27403

Answer is D right?

C

 

[TheStallion-Reborn]

The ans is C. Donno why acceleration decreases

air resistance

 

[sourov97]

pls explain!

 

[farhan141]

View attachment 27407
pls explain!

C?

 

[sourov97]

yes!!why!

 

[Saad Mughal]

View attachment 27407
pls explain!

The resistance increases so the voltage across the RESISTOR increases, this means that a lower voltage is supplied against the capacitor which means that it will charge and discharge slowly and hence, less often.

 

[Saad Mughal]

yes!!why!

The answer should be B.

 

[sourov97]

The answer should be B.

sorry! yes u r right! he was wrong!

 

[sourov97]

The answer should be B.

but can u pls explain what it the function of capacitor!

 

[Saad Mughal]

but can u pls explain what it the function of capacitor!

It is a time delay SWITCH in terms, since it first charges (to its capacitance) and then allows current to pass through it.

 

[sourov97]

It is a time delay SWITCH in terms, since it first charges (to its capacitance) and then allows current to pass through it.

so according to the question it needs 110V to charge it up...then y would the lamp even light if the capacitor is not getting 110V..(if R of the resister increases then V also incerases..which decreases the V accross the capacitor ,, right???)

 

[papajohn]

so according to the question it needs 110V to charge it up...then y would the lamp even light if the capacitor is not getting 110V..(if R of the resister increases then V also incerases..which decreases the V accross the capacitor ,, right???)

Now more time to accumulate the charges.

 

[Saad Mughal]

so according to the question it needs 110V to charge it up...then y would the lamp even light if the capacitor is not getting 110V..(if R of the resister increases then V also incerases..which decreases the V accross the capacitor ,, right???)

They're telling you the magnitude at which the capacitor charges at first, this is a hint.
When 110 V is supplied the capacitor will charge in.. say, 2 minutes whereas when a voltage of 80 V is applied (resistance increased in potential divider), the capacitor will charge in.. say, 3 minutes. This means that it's charging time will increase and the bulb will go on and off less frequently.

 

[sourov97]

They're telling you the magnitude at which the capacitor charges at first, this is a hind.
When 110 V is supplied the capacitor will charge in.. say, 2 minutes whereas when a voltage of 80 V is applied (resistance increased in potential divider), the capacitor will charge in.. say, 3 minutes. This means that it's charging time will increase and the bulb will go on and off less frequently.

thanks...got it!

 

[Mohammad Farzanullah]

can any1 plz answer this question! this is from a physics past ppr in Oct 10!

Explain, in outline, how a low-density cloud of hydrogen in space becomes a star.