Explanation

 At the open end of an organ pipe, antinodes are formed. CK-12 Foundation

An antinode is a point of maximum displacement in a standing wave,

And since the air molecules at the open end of an organ pipe can vibrate freely, they create an antinode there. 

Explanation

When an object is placed at the focus of a convex lens, the refracted rays become parallel.

These rays do not converge to form a real image.

So technically, the image is formed at infinity and is real, inverted, and highly enlarged.

Therefore, the image will be real, formed at infinity.

Explanation

Thermistors are temperature-sensitive resistors whose resistance changes with temperature.

This change affects the electrical voltage in a circuit, allowing temperature measurement.

Explanation

In a Cathode Ray Oscilloscope (CRO), the brightness of the spot is controlled by the intensity of the electron beam.

This intensity is regulated by the voltage on the anodes, hence anodes control brightness.

Explanation

Back e.m.f. is directly proportional to the speed of the motor.

As the motor speed increases, the back e.m.f. also increases.

Explanation

Eddy currents are circular currents induced in conductors when exposed to a changing magnetic field.

They flow in loops perpendicular to the magnetic flux that induces them.

Explanation

When an electron from a higher shell fills a vacancy in an inner shell, it emits a photon with a specific energy.

These are called characteristic X-rays because their energy depends on the atomic structure of the element.

Explanation

A solid-state detector is essentially a PN junction that detects radiation by generating charge carriers.

Incoming particles or photons produce electron-hole pairs in the depletion region of the PN junction.

Explanation

A proton is made of two up quarks and one down quark (uud).

This combination gives the proton its positive charge (+1).

Explanation

Hadrons are particles that participate in strong nuclear force and include protons, neutrons, and heavier particles.

They are generally equal to or heavier than protons in mass.