Q.31)-Who is the inventor of RADAR?
- H.N. Van Tessel
- William K. Rontgen
- P.T. Farnswarth
- A.H. Taylor and Lio C. Young
Q.32)-Who discovered X-Rays?
- Roentgen
- Becquerel
- Marie curie
- Wan Loo
Q.33)-X-Rays can be used.
- To detect defects in precious stones and diamonds
- To detect heart diseases
- To detect gold under the earth
- For cutting and welding of metals
Q.34)-Wavelength of visible spectrum is_______
- 1300 A - 3000 A
- 3900 A - 7600 A
- 7800 A- 8000 A
- 8500 A - 9800 A
Q.35)-In a Filament type Light bulb most of the electric power consumed appear as___________
- Visible Light
- Infrared Light
- Ultraviolet
- Fluorescent Light
Q.36)-Which of the following is used in MRI machine?
- Sound wave
- X-Rays
- Ultrasonic wave
- Magnetic wave
Q.37)-A wavelength of 0.3 m is produced in air and it travels at a speed of 300 m/s. Then it will be an-
- Audible wave
- Ultrasonic
- Microwave
- Infrasonic
Q.38)-Bolometer is used to measure which of the following?
- Frequency
- Temperature
- Velocity
- Wavelength
Q.39)-Coolidge tube is used to produce
- Radio waves
- Micro waves
- X-Rays
- Gamma Rays
Q.40)-Which of the following parts of the sunlight makes the solar cooker hot?
- Ultraviolet
- Red Light
- Infrared
- Cosmic rays