Questions

A device which is used to convert light energy directly into electrical energy is called as photovoltaic cell or a solar cell.

Heliostats convert light energy into heat energy.

A thermocouple is a device for measuring temperature.

The International Waste Picker's Day is observed on 1st March in memory of the massacre in Colombia in which 11 workers were brutally killed University of Barranquilla.

Former cricketer Ravi Shastri has been named the New coach of Team India on a Two year contract.

This will be Shastri's second stint with the team, after being the director from 2014 - 2016.

It is ABACUS.

Words formed are as below 

BUS
CAB
CUB
US

BRICS is basically an association of 5 major emerging national economies: Brazil, Russia,China, India and South Africa.

BRIC was coined in Foreign Ministerial meeting of Brazil,Russia,China and India in Newyork in Sept 2006. BRIC officialy came in existance in 2009 at Yekaterinburg,Russia.

At start group was named as BRIC, but after being formally invited by the BRIC countries to join the group, South Africa officially became a member nation on 24 December 2010, and the group was renamed BRICS.