Which of the following statements is correct for a compound microscope?

On an equipotential surface :

A. Transformers can not be used to step up DC.
B. The frequency of output across the secondary is always equal to the frequency of input across the primary.
C. The output power of a transformer may be increased to a value which is more than the input power.
D. Transformation ratio is equal to turns ratio.
E. In a step up transformer, secondary current is less than primary current.
Choose the correct answer from the options given below:

The frequency of a photon whose energy is 66.3 eV would be
(Given \( h = 6.63 \times 10^{-34} \text{ Js} \))

Using the given information, calculate the mass defect of the \({ }_8^{16} O\) nucleus in \(MeV / c ^2\).
Mass of electron, \(m_e=0.00055 u\)
Mass of proton, \(m_p=1.00727 u\)
Mass of neutron, \(m_n=1.00866 u\)
Experimental mass of nucleus \(=15.99053 u\)
\(1 u=931.5 MeV / c^2\)
Choose the correct answer from the options given below:

If a wave gets refracted into a denser medium, which of the following is true?

Two Polaroids are placed in such a way that their axes make an angle of 60° with each other. If an unpolarized light is incident on a system of these Polaroids, the fraction of transmitted light to the incident light will be

Match List I with List - II.

List - 1	List - II
(A) Biocontrol agent	(I) Aphids
(B) Mycorrhiza	(II) Methanobacterium
(C) Ladybird	(III) Trichoderma
(D) Biogas	(IV) Glomus

Choose the correct answer from the options given below :

A solution of \(CuSO_4\) is electrolysed for \(10\ min\) with a current of \(1.5\ A\).
What is the mass of copper deposited at the cathode?
(Molar mass of \(Cu = 63\ g\ mol^{-1}\), \(1F = 96487\ C\))

Match List-l with List-II

LIST-I	LIST-II
A. Planck's constant	(I) \(\left[M L^2 T^{-2}\right]\)
B. Work function	(II) \([L]\)
C. Stopping potential	(III) \(\left[M L^2 T^{-3} A^{-1}\right]\)
D. de Broglie wavelength	(IV) \(\left[M L^2 T^{-1}\right]\)

Choose the correct answer from the options given below :

The light of wavelength 600 mm is coming from a star. What is the limit of resolution of a telescope whose objective has a diameter of 2.54 m ?

Identify the hormone releasing IUDs -

We use microbes and microbially derived products almost every day. Bacteria called lactic acid bacteria (LAB) grow in milk to convert it into curd. The dough, which is used to make bread, is fermented by yeast called Saccharomyces cerevisiae. Microbes are used to produce industrial products like lactic acid, acetic acid and alcohol, which are used in a variety of processes in the industry. However, certain bacteria, which grow anaerobically on cellulosic material, produce large amount of methane along with CO2 and H2. These bacteria are collectively called methanogens, and one such common bacterium is Methanobacterium. These bacteria are commonly found in the anaerobic sludge during sewage treatment. Microbes are also used for commercial and industrial production of certain chemicals like organic acids, alcohols and enzymes.
Examples of acid producers are Aspergillus niger (a fungus) of citric acid. You are familiar with the commonly used antibiotic Penicillin. Do you know that Penicillin was the first antibiotic to be discovered, and it was a chance discovery? Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol.
Statins produced by the yeast Monascus purpureus have been commercialised as blood-cholesterol lowering agents. It acts by: