Semiconductor Electronic: Material, Devices And Simple Circuits — Physics STD 12 Science — Question

The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light:

Equipotential surfaces associated with an electric field which is increasing in magnitude along the x-direction are(a) Planes parallel to yz-plane(b) Planes parallel to xy-plane(c) Planes parallel to xz-plane(d) Coaxial cylinders of increasing radii around the x-axis

Nuclear forces are:

Same as problem 4 except the coil A is made to rotate about a vertical axis (Fig). No current flows in B if A is at rest. The current in coil A, when the current in B (at t = 0) is counterclockwise and the coil A is as shown at this instant, t = 0, is:

Statement -1: NAND and NOR gates are called digital building blocks.
Statement-2: The repeated use of NAND (or NOR) gates can produce all the basis or complicated gates.

Atoms of an element differing in mass though possessing the same chemical properties are called :

A diminished virtual image can be formed only in(a) Plane mirror(b) A concave mirror(c) A convex mirror(d) Concave-parabolic mirror

A given charge is situated at a certain distance from an electric dipole in the end-on position experiences a force F. If the distance of the charge is doubled, the force acting on the charge will be(a) 2F       (b) F / 2(c) F / 4(d) F / 8