The speed of a line printer is measured in which unit?
- A.LPM
- B.DPI
- C.PPM
- D.CPS
Correct answer
Explanation
The correct answer is A, LPM, lines per minute. A line printer, such as a drum or chain printer, sets up and prints a whole line of characters at one stroke, so counting the lines it finishes in a minute is the natural measure of its speed.
Option B, DPI, dots per inch, is not a speed unit at all: it measures the quality of the print, that is, how finely the dots are packed. Option C, PPM, pages per minute, belongs to page printers such as the laser printer, which prepares an entire page before printing it. Option D, CPS, characters per second, belongs to character printers such as the dot matrix and the daisy wheel, which print a few characters at a time. The three speed units line up with the three classes of printer, character, line and page, and the odd one out in this set is always the quality unit DPI.
Read the full article: Input and Output Devices: Types, Examples and MCQs
Practice Questions
View allWhich of the following is both an input and an output device?
- A.Scanner
- B.Plotter
- C.Touchscreen
- D.Light pen
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A touchscreen accepts a finger tap or a stylus stroke as input and displays the result on the very same surface, so the one piece of hardware performs both jobs.
Read the full explanation →Who invented the computer mouse?
- A.Douglas Engelbart
- B.Charles Babbage
- C.Jack Kilby
- D.Christopher Latham Sholes
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He built the first mouse, a small wooden box with a pair of wheels underneath, at the Stanford Research Institute, and the patent describes it as an X-Y position indicator for a display system.
Read the full explanation →Which of the following is an impact printer?
- A.Laser printer
- B.Inkjet printer
- C.Dot matrix printer
- D.Thermal printer
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Its print head carries a column of tiny pins that strike an inked ribbon against the paper, forming each character out of dots.
Read the full explanation →MICR technology is used mainly in which of the following?
- A.Processing of bank cheques
- B.Reading objective answer sheets
- C.Billing at a retail counter
- D.Recording fingerprints
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MICR stands for Magnetic Ink Character Recognition. The line of characters printed along the foot of a cheque is set in magnetic ink in the E-13B font, and the reader identifies each character from its magnetic signal, so the cheque is sorted correctly even when it has been folded, stamped…
Read the full explanation →The smallest element of a picture displayed on a computer screen is called a
- A.Bit
- B.Pixel
- C.Byte
- D.Dot pitch
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The word is a contraction of picture element. A screen image is a grid of these points, and the number of them across and down the screen is what is quoted as the resolution of the monitor, so a higher pixel count means a finer picture.
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