Earthworms have no skeleton,but during burrowing the anterior end becomes turgid and acts as a hydraulic skeleton. It is due to

$A$ magnet makes $40$ oscillations per minute at a place having a magnetic field of $0.1 \times 10^{-5} \, T$. At another place, it takes $2.5 \, s$ to complete one vibration. The value of the Earth's horizontal magnetic field at that place is:

Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest $pH$?

Which one of the following frequencies of radiation (in $Hz$) has a wavelength of $600 \ nm$?

At a certain place,the angle of dip is $60^{\circ}$ and the horizontal component of the earth's magnetic field $(B_H)$ is $0.8 \times 10^{-4} ~T$. The earth's overall magnetic field is

Heating chloroform with aqueous sodium hydroxide solution forms