Answer: (i) armed forces : Echoes are used of the military discover the new firearm position out-of adversary

Answer: (i) armed forces : Echoes are used of the military discover the new firearm position out-of adversary
In case the rate from sound was 334 ms-step step one, determine time in he hears an echo

  1. armed forces,
  2. geologists,
  3. fishermen.

Answer: t = 0

Radar an instrument is utilized to obtain an enemy air-pastime ship. (ii) geologists : Echoes are utilized by the geologists having nutrient to generate leads. (iii) anglers : for finding fishes ultrasonic surf are sent with the liquids. If these types of oscillations hit a seafood, he’s reflected to the latest receivers. Committed getting hearing the fresh new echoes recorded. The position of seafood was calculated by the d = v ? t/dos playing with vel. from voice in water because 1450 ms -step one .

Matter step one. Brand new program according to research by the meditation out-of sound are: (a) megaphone (b) sounding-board (c) sonometer (d) one another (a) and (b) Answer: (d) one another (a) and (b)

Matter dos. That’s not the issue into the formation from echoes ? (a) Lowest range within way to obtain sound and you may showing looks would be to become 17 meters. (b) The heat out-of sky would be a lot more than 20°C. (c) Brand new wavelength out-of voice can be below the best norwegian dating sites fresh new level away from brand new highlighting body. (d) The brand new concentration of sound will be adequate so it you’ll be read after reflection. Answer: (a) Lowest length between the source of voice and you can reflecting muscles should getting 17 yards.

Concern step three. For reading an echo, the minimum distance within supply of sound and you will highlighting muscles are (a) twelve m (b) twenty-four yards (c) 17 yards (d) 51 meters Answer: (c) 17m

Concern cuatro. To track down its target on darkness this new owl or even the bat gives off: (a) infrasonic swells (b) ultrasonic surf (c) sonic waves (d) infrared waves Answer: (b) ultrasonic swells

Concern step one. One fireplaces a gun before an establishing 167 m away. Answer: d = 167 ? 2d = 167 ? dos m Speed off voice = 334 ms -1 t to have echo to get heard = ?

Concern dos. An echo is read after 0.8 s, when a guy fireplaces a cracker, 132.8 yards of a high building. Determine the rate of sound. 8 s d = 132.8 meters

Concern 3. The speed away from sound is 310 ms -step 1 . A guy fires a gun. A mirror was read immediately after step 1.5 s. Assess the length off individual from the cliff from which echo is actually read. Answer: Rate out of sound = 310 ms -1 time after which reflect is actually heard t = step 1.5 s length of cliff d = ? 2d = Rate ? t

Question 1. An echo is read of the a great radar inside 0.08 s. When the speed from radio waves are 3 ? ten 8 ms -step 1 , what lengths ‘s the enemy jet ? 08 s v = step three ? 108 ms -step 1

Matter dos. An enemy airplanes is at a distance out of 300 km regarding a good radar. In how much tangerine the newest radar should be able to select the newest plane ? Get speed out-of radiowaves given that 3 ? 10 8 ms -step 1 . Answer: d=3 hundred t = ? v = step 3 ? 10 8 ms -step 1 t=2d/v = 2 ? 300 ? 1000m/step three ?10 8 ms -step 1 =0.002 s = 2 ? 10 -step 3 s

Question 1. A man stands in between two parallel cliffs and explodes a cracker. He hears the first echo after 0.6 s and second echo after 2.4 s. Calculate the distance between the cliffs. [Speed of sound is 336 ms -1 ] Answer: Let the 2 buildings A and B situated at a distance d1 and d2 from a man’s point.