English
Hindi

Question

Download Solution PDF

A radar is able to detect the reflected waves from an enemy's aeroplane after a time interval of 0.02 × 10−3 sec. If the velocity of the waves is 3 × 108 m/s. The distance of the aeroplane from the Radar will be :

This question was previously asked in
HTET TGT Science 2021 Official Paper
Download PDF Attempt in App
View all HTET Papers >
  1. 1.0 km
  2. 1.5 km
  3. 3.0 km
  4. 6.0 km

Answer (Detailed Solution Below)

Option 3 : 3.0 km
Free Tests
View all Free tests >
Free
HTET PGT Official Computer Science Paper - 2019
60 Qs. 60 Marks 60 Mins
Start Now

Detailed Solution

Download Solution PDF

Concept:

Let 'd' m be the distance of the aeroplane from the radar.

Then, distance travelled by the reflected sound to reach the radar = 2d

Relation between Speed, Time, Distance:

Calculation:

Given:

t = 0.02 × 10-3 sec, c = 3 × 108 m/s.

∴ d = 3000 m = 3 km.

Download Solution PDF
Latest HTET Updates

Last updated on Jun 6, 2025

-> The HTET TGT Applciation Portal will reopen on 1st June 2025 and close on 5th June 2025.

-> HTET Exam Date is out. HTET TGT Exam will be conducted on 26th and 27th July 2025

-> Candidates with a bachelor's degree and B.Ed. or equivalent qualification can apply for this recruitment.

-> The validity duration of certificates pertaining to passing Haryana TET has been extended for a lifetime.

-> Enhance your exam preparation with the HTET Previous Year Papers.

Exams Tests Super Practice

More The speed of a travelling wave Questions

Q1.Which of the following equations represents a travelling wave?
Q2.A radar is able to detect the reflected waves from an enemy's aeroplane after a time interval of 0.02 × 10−3 sec. If the velocity of the waves is 3 × 108 m/s. The distance of the aeroplane from the Radar will be :
Q3.Which of the following equations represents a travelling wave?
Q4.When a ray of light enters a glass slab from air, then:
Q5.A wave of wavelength 0.60 cm is produced in air and it travels at a speed of 300 ms-1 What will be the frequency of the wave ?
Q6.What will be the wavelength of a wave that is produced in air and travels at a speed of 300 ms-1 at the frequency of 60,000 Hz?
Q7.In which of the following medium sound would have maximum speed?
Q8.A mild steel plate has a thickness of 20 mm. An ultrasonic pulse travels in it with a velocity of 18000 kmph. The echo time of the pulse will be 
Q9.Which of the following best represents the variation of frequency of vibration 'ν' with the radius of cross section 'r' of a stretched string?

More Waves Questions

Q1.Which of the following equations represents a travelling wave?
Q2.______ are used in radiotherapy.
Q3.What is the frequency of an object if we know that it oscillates 100 times in 5 seconds? 
Q4.What is not correct about ultrasonic waves ? 
Q5.If the speed of a sound wave is 340 m/s and its frequency is 1700 HZ, then wavelength (λ) for this wave in cm will be
Q6.The distance between one wave crest to the next or from trough is called
Q7.The flash of lightning is seen before the thunderstorm is heard. It verifies that
Q8.The streaming of light beams coming from the Sun through trees is said to have suggested that light travels in straight line. The particles on the path of light beams are visible to us because
Q9.Which of the following statements is not correct about quality factor of a parallel resonance circuit?
Q10.From the wave equation \(\rm y = 0.5 \sin \frac{2\pi }{3.2} (64t - x)\) the frequency of the wave is
Suggested Test Series
View All >
HTET TGT Level 2 - 2024 Mock Test
183 Total Tests with 10 Free Tests
Start Free Test
Social Science (SST) Content for All Teaching Exams - Let's Crack TET!
191 Total Tests with   1 Free Tests
Start Free Test

More Physics Questions

Q1. A bar magnet has total length 2l = 20 units and the field point P is at a distance d = 10 units from the centre of the magnet. If the relative uncertainty of length measurement is 1%, then uncertainty of the magnetic field at point P is : 
Q2.A bi-convex lens is constructed using two thin plano-convex lenses, as shown in the figure. The refractive index of the first lens is 1.5, and that of the second lens is 1.2. Both curved surfaces have the same radius of curvature, R = 14 cm. For this bi-convex lens, when the object distance is 40 cm, determine the image distance:
Q3.In a closed system of two interacting particles, m1 and m2, the center of mass is stationary. Given the trajectory of m1 and that m2 = m1, determine the trajectory of m2.
Q4.Match the following entries in column-I and column-II with respect to an oscillating spring-block system: Column-I Column-II (a) Mass of the block is doubled (i) Energy of oscillation becomes 4 times (b) Spring constant is made 4 times (ii) Speed of block becomes 2 times (c) Amplitude of oscillations is doubled (iii) P.E. becomes 4 times (d) Angular frequency is doubled (iv) Time period becomes √2 times (e) length of spring is quadrupled (v) Time period becomes 2 times
Q5.Consider the process of one mole of monatomic ideal gas shown in the T-V diagram. The correct match is based on the following equations and principles: Column - 1 Column - 2 (I) Work done in the isothermal process (1 → 2) (i) (RT0 / 3) ln 2 (II) Change in internal energy (1 → 2 → 3) (ii)RT0 (III) Total heat absorbed (1 → 2 → 3) (iii)  (RT0 / 3) [3 + ln 2] (IV) Heat absorbed in the isothermal process (1 → 2) (iv)  (RT0 / 5) ln 2 (V) Work done in the process (1 → 2→ 3) (v) RT0 /2  
Q6.For the LCR AC circuit (resonance frequency ωo) shown in the figure below, choose the correct statement(s). List 1 List 2 (i) ω0 a) depends on L,C (ii) At ω =ω0 , VR is   b) independent of L, C (iii) VR and I are  c) In phase (iv)  At ω =ω0 /2, VR is   d) Out of phase  
Q7.Match the Following: Match the entries from Column-1 with their corresponding descriptions in Column-2 and numerical values in Column-3. Column - 1 Column - 2 Column - 3 (I) Planck’s radiation law (i) Peak wavelength shifts inversely with temperature (P) 0.5 (II) Stefan-Boltzmann law (ii) Energy radiated is proportional to the fourth power of temperature (Q) 0.25 (III) Kirchhoff’s Law of Radiation (iii) Absorptivity equals emissivity in thermal equilibrium (R) 0.3 (IV) Newton’s Cooling Law (iv) Rate of cooling is proportional to the temperature difference (S) 0.4   A surface reflects 70% of the incident energy. Determine the most appropriate match for its emissivity.  
Q8.A ball of 8 kg, moving at 15 m/s, enters a 22 kg spring gun at rest. If the surfaces are frictionless and the spring is massless, determine the gun's speed after the ball stops moving relative to the gun.
Q9.A square frame is constructed from four uniform rods. The rods, AB, BC, CD, and DA, have masses 2m, 3m, 4m, and 5m respectively, and each has a length of 2a.  Where is the center of mass of this frame located in the x-y plane, specifically, which quadrant or region defined by x and y coordinates.
Q10.Imagine you have a cup of Starbucks coffee in a moving car. If the car suddenly brakes
Testbook Edu Solutions Pvt. Ltd.
1st & 2nd Floor, Zion Building,
Plot No. 273, Sector 10, Kharghar,
Navi Mumbai - 410210
support@testbook.com
Toll Free:1800 833 0800
Office Hours: 10 AM to 7 PM (all 7 days)
Company
About usCareers We are hiringTeach Online on TestbookPartnersMediaSitemap
Products
Test SeriesTestbook PassOnline CoursesOnline VideosPracticeBlogRefer & EarnBooks
Copyright © 2014-2022 Testbook Edu Solutions Pvt. Ltd.: All rights reserved
User PolicyTermsPrivacy
Hot Links： teen patti star login teen patti party teen patti yes teen patti vip teen patti gold real cash