A radioactive source (Phosphorus-32) has an initial activity 10 \(\mu\)Ci, its half life is 14 days. What time elapses before the activity falls to 1.25 \(\mu\)Ci ?

Voltage sensitivity of a moving coil galvanometer doesn't depend on :

Motion of a charged particle having velocity v in a uniform magnetic field B is circular, if v is

An object of length 2.0 cm is placed at a distance of 1.5 f from a concave mirror where f is the magnitude of the focal length of the mirror. The length of the object is perpendicular to the principal axis. The length of the image will be

In terms of Bohr radius \( a_0 \), the radius of the 2nd Bohr orbit ofHydrogen is:

A parallel beam of light of wavelength 500 nm is incident normally on a slit of width d. If the distance between slit and screen is 0.6 m and distance of second order minimum from the centre of the screen is 6.0 mm, What is the width of the slit?

Which of the following examples are based upon the total internal reflection of light?
(A) Optical fibre
(B) Twinkling of stars
(C) Mirage
(D) Sparkling of diamond
Choose the correct answer from the options given below:

If 'n' identical resistors, each of value 'R' are first connected in series to a battery of emf 'E' and internal resistance 'R', the current drawn is 'I'. Now if they are connected in parallel, then the current drawn is '5 I'. The value of n is

Match List-I with List-II

List-I (Vitamins)	List-II (Diseases)
(A) Vitamin K	(I) Pernicious anaemia
(B) Vitamin A	(II) Osteomalacia
(C) Vitamin B12	(III) Increase blood clotting time
(D) Vitamin D	(IV) Night blindness

Choose the correct answer from the options given below:

Read the passage carefully. Attempt the questions.
In our body, cell growth and differentiation is highly controlled and regulated. In cancer cells, there is breakdown of these regulatory mechanisms. Cancerous cells just continue to divide giving rise to masses of cells called tumors. Benign tumors normally remain confined to their original location. The malignant tumors, on the other hand are a mass of proliferating cells. These cells actively divide and starve the normal cells by competing for vital nutrients. Cells sloughed from such tumors reach distant sites through blood, and wherever they get lodged in the body, they start a new tumor there. This property is called metastasis. Transformation of normal cells into cancerous cells may be induced by physical, chemical or biological agents called carcinogens.
Cancer is caused by:
A. Carcinogens
B. Protein rich foods
C. Primary lymphocytes
D. Oncogenes
Choose the correct answer from the options given below:

Which of the following statement(s) is/are TRUE?
(A) Skew symmetric matrix of even order is always symmetric
(B) Skew symmetric matrix of odd order is non-singular
(C) Skew symmetric matrix of odd order is singular
(D) Skew symmetric matrix is always square matrix
Choose the correct answer from the options given below:

For a reaction \(A \rightarrow C + D\), the initial concentration of \(A\) is \(0.010\ M\).
After \(100\ s\), the concentration of \(A\) is \(0.001\ M\).
The rate constant has numerical value 9.0.
The order of reaction is:

E and V, respectively, denote electric field intensity and electrostatic potential at a point. The correct relation between the two is