Where is a periscope used?
Uses Of Periscope It is used in submarines to determine the distance of a torpedo and helps in deciding the right time for the attack. It is used in a nuclear reactor to observe the chemical reactions that are taking place. In military periscopes are used to observe from their hiding position.
What is a periscope for Class 7?
A periscope is a long, tubular device through which a person can see objects that are out of the direct line of sight. The periscope makes use of two plane mirrors to see over the top of things.
What is periscope instrument?
A periscope is an optical instrument that uses a system of prisms, lenses or mirrors to reflect images through a tube. Light from a distant object strikes the top mirror and is then reflected at an angle of 90 degrees down the periscope tube.
Why is it called periscope?
periscope (n.) viewing apparatus on a submarine, by which objects in a horizontal view may be seen through a vertical tube, 1899, formed in English from peri- “around” + -scope “instrument for viewing.” Earlier (1865) a technical term in photography.
What is the principle of periscope?
A periscope is a useful example of the law of reflection at work. It’s important that your mirrors are placed at a 45° angle, because light always reflects away from a mirror at the same angle that it hits it. In a periscope, light from an object strikes the top mirror at 45° and bounces off at the same angle.
Is Brusque a bad word?
Meaning of brusque in English. quick and rude in manner or speech: His secretary was a little brusque with me.
What does accost mean?
transitive verb. : to approach and speak to (someone) in an often challenging or aggressive way He was accosted by a stranger on the street.
Is off hand a correct English?
“Offhand” (also hyphenated: “off-hand”) is typically used to mean “without much effort,” “without thinking about it at length,” etc. – “How long will it take you to write the report?” “Offhand, I would say two hours.” “Off the top of my head” (but not “offhead”) has the same meaning.
Is hand on or off hand?
The adjective offhand describes a remark or comment that is made without previous thought or preparation. If you are at a wedding, you may want to make a few offhand but nice remarks about the newlyweds. As an adjective, offhand can mean careless, brusque, or inconsiderate.
How do you use offhand in a sentence?
Offhand sentence example Natasha suddenly shrank into herself and involuntarily assumed an offhand air which alienated Princess Mary still more. Her offhand treatment of the new empress, Marie Louise, in 1810 led to her removal from court. Fred dismissed her observation with an offhand attempt to romanticize the time.
Do you remember off hand?
Meaning: Off-hand means without preparation. People say that they don’t know the answer off-hand, meaning that they don’t know it at that time.
What is an offhand voice?
an offhand tone of voice2 said or done without thinking or planning an offhand remark —offhandedly adverb —offhandedness noun [uncountable]Examples from the Corpusoffhand• There is sometimes a stage in the tone 2 are where the patient begins to be offhand and flippant.
What is the meaning of in hot water in idioms?
(also get into hot water) to be in or get into a difficult situation in which you are in danger of being criticized or punished: He found himself in hot water over his comments about immigration.
What process is heating the water?
Convection is the main method of heat transfer in fluids such as water and air.
What Does It doesn’t hold water mean?
phrase. If an argument or theory does not hold water, it does not seem to be reasonable or be in accordance with the facts.