Identify the correct statements among the following.
(A) Electrical appliances in a household are always connected in series.
(B) Electrical appliances in a household are always connected in parallel.
(C) The potential difference across different electrical appliances in households is not equal.
(D) The potential difference across different electrical appliances in households is equal.
Choose the correct answer from the options given below:

The speed of electromagnetic waves in a material medium is given by (symbols have their usual meanings):

X-rays of wavelength \( = 1\text{\AA} \) have frequency

A monochromatic visible light consists of

There are two thin parallel charged sheets having surface charge density \( \sigma \) placed at a small distance apart. Which of the following statements are correct?
(A) If both the sheets are positively charged, then the electric field between them is \( \sigma/\epsilon_0 \)
(B) If both the sheets are negatively charged, then the electric field between them is \( \sigma/\epsilon_0 \)
(C) If the left sheet is positively charged and the right sheet is negatively charged the field between them is \( \sigma/\epsilon_0 \)
(D) If the right sheet is positively charged and the left sheet is negatively charged then the field between them is \( \sigma/\epsilon_0 \)
Choose the correct answer from the options given below:

The overhead horizontal power transmission line carries a current of 75 A from east to west direction. The magnetic field above it at a vertical distance of 1.2 m will be

In photoelectric effect, the stopping potential depends on the

The circuits where transformers are used :

Gabriel synthesis is used for the synthesis of:

Bt toxin is expressed in plants to provide resistance to insects; hence used as a bio-pesticide. Select the correct examples of Bt plants:
(A). Bt Cotton
(B). Bt Rice
(C). Bt Peas
(D). Bt Corn
Choose the correct answer from the options given below:

Huygen's wave theory of light could not explain the phenomenon of :

An alpha particle is moving in a magnetic field \( (3\hat{i} + 2\hat{j}) \text{ T} \) with the velocity \( (7 \times 10^5 \hat{i}) \text{ m/s} \). The magnetic force acting on the particle is:

The resistance of a potentiometer wire of length 4 m is \( 10 \ \Omega \).
A resistance box and a 2 V accumulator are connected in series with it.
What resistance should be introduced in the box to have a potential drop of \( 1 \ \mu\text{V/mm} \) along the potentiometer wire?