Current Affairs Question - 22 July 2020

Explanation :

• Article 72 and Article 161 empowers the President and the Governors respectively, the power to grant pardons, reprieves, respites or remissions of punishment or to suspend, remit or commute the sentence of any person convicted of any offence.
• Remission: It implies reducing the period of the sentence without changing its character. For example, a sentence of rigorous imprisonment for five years may be remitted to rigorous imprisonment for one year.
• Respite: It denotes awarding a lesser sentence in place of one originally awarded due to some special fact, such as the physical disability of a convict or the pregnancy of a woman offender.
• Reprieve: It implies a stay of the execution of a sentence (especially that of death) for a temporary period. Its purpose is to enable the convict to have time to seek pardon or commutation from the President.

Explanation :

P-waves

• These are the first waves detected by seismographs (instruments used to detect and record earthquakes).
• These are longitudinal waves which means they vibrate along the same direction as they travel.
• Examples of longitudinal waves include sound waves and waves in a stretched spring.

S-waves

• These waves arrive at the detector after primary waves.
• These are transverse waves which means they vibrate at a right angle to the direction in which they travel.
• Examples of transverse waves include light waves and water waves.

Difference

• Both types of seismic waves can be detected near the earthquake centre but only P-waves can be detected on the other side of the Earth.
• P-waves can travel through solids and liquids (since they are longitudinal waves) whereas S-waves can only travel through solids (as they are transverse waves).
• This means the liquid part of the core blocks the passage of S-waves.