The current in a resistive series circuit is 7.0 A. On adding a resistance of 1.6 \( \Omega \) in the same circuit in series, the current drops to 5.0 A. The original resistance of the circuit is :

A p-type semiconductor can be obtained by adding

Two identical metal balls, A and B, with similar charges Q are suspended with insulating threads. They repel each other with a force F. Another identical uncharged metal ball C is first touched with metal ball A and then touched with metal ball B and finally removed. The new force of repulsion between A and B will be

Two slits are kept 1 mm apart and the screen is placed 1.0 m away. What is the fringe separation when blue-green light of wavelength 500 nm is used ?

Two cells of emf 10 V and 6 V, each having internal resistances of \(2 \Omega\) are connected in parallel across points A and B. The equivalent emf of the cells is

A Convex mirror produces the magnification \( \frac{1}{3} \) and \( \frac{1}{4} \) when the object is placed at the points P and Q in front of the mirror.

The correct arrangment of colours in the descending order of their wavelength is
A. Green
B. Orange
C. Yellow
D. Violet
E. Red
Choose the correct answer from the options given below:

The electric field vector \( \vec{E} \) and magnetic field vector \( \vec{B} \) in electromagnetic waves are :

If \(f(x)=\left\{\begin{array}{ll}\frac{\sin \pi x}{5 x}, & x \neq 0 \\ k, & x=0\end{array}\right.\) is continuous at \(x=0\), then \(k\) is :

Read the following paragraph carefully and answer the given questions.
Certain types of leukocytes (WBC) of our body like polymorpho-nuclear leukocytes (PMNL-neutrophils) and monocytes and natural killer (type of lymphocytes) in the blood as well as macrophages in tissues can phagocytose and destroy microbes. For determining the cause of allergy, the patient is exposed to or injected with very small doses of possible allergens, and the reactions studied. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Heroin, commonly called smack is chemically diacetylmorphine which is a white, odourless, bitter crystalline compound. This is obtained by acetylation of morphine. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs. Different species of Plasmodium (P. vivax, P. malaria and P. falciparum) are responsible for different types of malaria. Of these, malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal.
Heroin, commonly called smack is chemically __________ which is a white, odourless, bitter crystalline compound.

The probability of guessing correctly atleast 8 out of 10 answers on a true false type examination is :

For any 2 × 2 matrix, if \(A(\operatorname{adj} A)=\left[\begin{array}{cc}100 & 0 \\ 0 & 100\end{array}\right]\), then |A| is equal to:

Read the passage carefully and answer
Carbohydrates are essential for both plants and animals. Some common examples of carbohydrates are glucose, fructose, sucrose, glycogen, cellulose and starch. They form a major portion of our food. Honey has been used for a long time as an instant source of energy in Ayurvedic medicine. Carbohydrates are used as storage molecules in both plants and animals. The cell wall of bacteria and plants is made of cellulose. We use cellulose in the form of wood for making furniture and as cotton fiber for clothing. They also provide raw material for textiles, paper, lacquers, and breweries. Carbohydrates are classified as Monosaccharides, Oligosaccharides and Polysaccharides on the basis of their behavior towards hydrolysis.
Monosaccharides cannot be hydrolyzed further to simpler units whereas oligosaccharides can yield 2-10 units of monosaccharides on hydrolysis. Polysaccharides, which are non-sugars yield a large number of monosaccharide units on hydrolysis.
Answer the following questions about carbohydrates:
Identify a component of starch from among the following.