At sunrise and sunset the sun appears reddish due to

Light from a point source in air falls on spherical glass surface (n = 1.4 and radius of curvature 20 cm). The distance of light source from the glass surface is 150 cm, At what position is the image formed?

Seven lead accumulators, each of emf 2 V, and internal resistance \( 0.07 \text{ } \Omega \), are connected in series with an external resistance \( 9.51 \text{ } \Omega \). The current in the circuit is

In double-slits experiment using light of wavelength 550 nm, the angular width of a fringe formed on a distant screen is 0.2°, What is the spacing between the two slits?

A monochromatic source emitting light of wavelength 600 nm has a power output of 66 W. The number of photons emitted by the source in 2 minutes is: (Given: \( h = 6.6 \times 10^{-34} \text{ Js} \))

An alternating voltage \( V = V_0 \sin(\omega t + \pi/2) \) is applied across an ac circuit. As a result, a current \( I = I_0 \sin(\omega t + \pi/6) \) flows in it. The power factor of the circuit is

A converging lens is used to form image on a screen. When the lower half of the lens is covered by an opaque screen then, the correct statements are :
(A) Intensity of Image will decrease.
(B) Intensity of Image will increase.
(C) Complete Image will be formed.
(D) Half the Image will disappear.

Which one of the mentioned reasons does not cause the loss of biodiversity?

When \(CuSO_4\) solution is electrolysed using platinum electrodes, which of the following is true ?

Which of the following statements are TRUE?
(A) The variable \(t\) of \(t\)-distribution ranges from \(-\infty\) to \(\infty\).
(B) The probability curve of the \(t\)-distribution is symmetric about the line \(t=0\)
(C) The variance of the \(t\)-distribution is greater than one.
(D) As the number of degrees of freedom decreases, the \(t\)-distribution curve moves closer to the standard normal probability curve.
Choose the correct answer from the options given below :

Read the passage carefully and answer the questions
Optically active polyhydroxy aldehydes or ketones or molecules which provide such units on hydrolysis are called carbohydrates. They can be broadly classified as monosaccharides, disaccharides and polysaccharides depending on their behavior towards hydrolysis. They are also classified as reducing or non-reducing sugars. Another class of biomolecules is proteins which are polymers of twenty different amino acids linked by peptide bonds. Amino acids can be classified as acidic, basic or neutral depending on the relative number of amino and carboxyl groups in their molecule. The essential amino acids cannot be synthesized by our body and hence must be provided through diet. Nucleic acids are the polymers of nucleotides which in turn consist of a base, pentose sugar and phosphate. There are two types of nucleic acids namely, DNA and RNA which differ in the composition of sugar and a base.
Four bases present in RNA molecule are:

Arrange the following haloalkanes in decreasing order of boiling point - Chloromethane, Bromomethane, dibromomethane, bromoform

Propionibacterium sharmanii is used in making which of the following food item