physics

Which of the following electromagnetic wave has the longest wavelength?

A. radio-waves B. gamma rays C. infrared waves D. ultraviolet rays Correct Answer: Option A A. radio-waves

6 years ago

A lens that is thinner at the middle and thicker at the edges is?

A. diverging B. converging C. plano-convex D. converging meniscus Correct Answer: Option A A. diverging

6 years ago

When an object is placed at the principal focus of a concave mirror, the location of the image formed is?

A. between principal focus and pole B. between principal focus and centre of curvature C. at infinity D. at centre…

6 years ago

The following devices use plane mirrors in their operations, except?

A. periscope B. sextant C. kaleidoscope D. binoculars Correct Answer: Option D D. binoculars

6 years ago

The ability of a wave to spread around corners is called?

A. polarisation B. dispersion C. diffraction D. reflection Correct Answer: Option C C. diffraction

6 years ago

A certain wave has a speed of 20ms-1. If the frequency of the wave is 0.25Hz, calculate the distance between successive crests of the wave.

A. 5.0m B. 40.0m C. 50.0m D. 80.0m Correct Answer: Option D D. 80.0m Explanation λ = v/f = 20/0.25=80

6 years ago

Dew point is not affected by?

A. temperature B. wind C. the amount of water vapour in the atmosphere D. atmospheric pressure Correct Answer: Option D…

6 years ago

Specific heat capacity 36.4 Jkg-1 K-1 of a body means that when 36.4J of heat energy is supplied to a body of

A. mass 100kg the temperature rises by 1k B. mass 1kg, the temperature by 1000K C. mass 1kg, the temperature…

6 years ago

In a thermos flask, heat loss by radiation is minimized by the?

A. silvered surfaces B. vacuum within the doubled walls C. plastic stopper D. cork support Correct Answer: Option A A.…

6 years ago