How much time does a serial link of 64 Kbps take to transmit a picture with 540 pixels.?

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  • Aug 23rd, 2005

It takes 67.5 ms. 540 pixels (grey) would take 540 bytes. And the speed is 64Kbps or 8KBps.

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  • Apr 14th, 2006

Where the heck did you get 1 min 8 sec from?

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  • Jul 17th, 2006

can u plz explain the basic fundamental of these type of questions?

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  • Jul 20th, 2006

I think it depends upon the resolution of the PICTURE. If the picture is black and white then each pixel is represented by only 1 BIT and not a BYTE. If resolution is better then no of bits to represent a pixel will be more.

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  • Jul 25th, 2006

Considering todays standards, we must assume its a colour pixel.. Even if its not, standard communication now happens at byte-level..

540 pixels represent 540 bytes..

So, we need to transmit 540 bytes.. Speed of link given is 64Kbps (64 Kilo bits per second) .. This is the same as 64/8=8 Kile Bytes per second (8 KBps)

(Notice the capital B for bytes..)

So the time required to transfer would be 540/8000=67.5 secs

which is approx 1 min and 7.5 seconds


  • Oct 30th, 2006

Consider 64 Kbps to be velocity and 540 pixels (540 bytes) to be distance.

Hence, time required to transmit 540 bytes over 8KBps link is simply 540/8000 = 0.0675 sec

I do not know why everybody is answering 67.5 secs...

It takes 1 second to transmit 8000 bytes is the definition of 8KBps and since we are only transmitting 540 bytes, we need less than 1 sec to do this...

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  • Mar 14th, 2007

Hey 0.0675s is the ans. simple 540*8/(64*1000)

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  • Jun 26th, 2007

Guys when did 8kbytes become 8000bytes...
its 1024*8=8192bytes.

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arindam routh

  • Aug 6th, 2007

If we consider 540 pixel =540 bytes=540*8 bits.
Now per second we are transferring=64*1024bits
So 64*1024 bits are transferred in 1 sec.
Therefore for 540*8 bits we require=(1/(64*1024))*540*8
.0659 sec

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  • May 29th, 2008

if it is a colour picture each pixel is 3 bytes(RGB) so time taken is 540*3/8000
if it is black&white each pixel is 1 byte so time taken 540/8000

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  • Aug 18th, 2009

In transmission its considered as download and upload
so, we have 64kbps 
Divide by 8 to get the download speed so its 8kbps ie 8192 bits per sec
Now consider the image its 540Bytes convert into bits its 540*1024 = 552960
So divide both 552960 / 8192 = 67.5 sec
i.e., 1 min 7 secs

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  • Oct 21st, 2011

for gray 1 pixel = 1 byte.
for color 1 pixel = 3 byte;
64kbps =64 kilo bit per sec;
64kbps= 64/8 kilo byte per sec= 8000 byte per sec;
so 540 gray pixels, time=540/8000=0.067sec;
for color 540 pixels, time= 540*3/8000=0.202 sec;

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