Questions

without this centripetal force, circular motion is not possible. It acts radially towards the centre and if this force is removed there will be no circular motion but the revolving body will fly off at a tangent.

The Qatar Airways has launched the World’s longest scheduled commercial service to ply between Doha to Auckland. The inaugural service of Flight QR920 took off on February 5, 2017 from Doha and will take 16 hours and 20 minutes to travel 14,535 kilometers to reach Auckland in New Zealand.
This makes Qatar Airways to launch the World’s fastest and longest passenger service in terms of flying time. Prior to this, emirates launched the world’s longest non-stop scheduled commercial flight with a service from Dubai to Auckland, spanning 14,200 kilometres.

The gram formula mass of a compound is nothing but the molar mass.

The molar mass of K2CO3 (Potassium Carbonate) is given by

Atomic weights of individual elements are

K (Potassium) = 39 g

C (Carbon) = 12 g

O (Oxygen) = 16 g

Hence, that of K2CO3 = 39(2) + 12 + 16(3)

= 78 + 12 + 48

= 138.