Questions

i. The 'Swachh Survekshan 2017' survey results were recently announced by Urban Development Minister M Venkaiah Naidu. The total 434 cities of India were surveyed. Indore in Madhya Pradesh is India’s cleanest city while Gonda in Uttar Pradesh is the dirtiest.

ii. Gujarat has the maximum of 12 cities among the top 50 clean cities, closely followed by Madhya Pradesh with 11 and Andhra Pradesh with eight. Uttar Pradesh accounted for half of the bottom 50 cities in the cleanliness ranking.

Top 10 clean cities of India in 2017 are:

Indore (MP)
Bhopal (MP)
Visakhapatnam (Andhra Pradesh)
Surat (Gujarat)
Mysuru (Karnataka)
Tiruchirapally (Tamil Nadu)
New Delhi Municipal Council (New Delhi)
Navi Mumbai (Mumbai)
Tirupati (Andhra Pradesh)
Vadodara (Gujarat).

Top 5 Dirtiest cities of India (with Rank) in 2017 are:

Gonda (UP)- 434,
Bhusawal (Maharashtra)- 433,
Bagaha (Bihar)- 432,
Hardoi (Uttarakhand)- 431,
Katihar (Bihar)- 430.

Goa

A Slip ring is a ring in a dynamo or electric motor which is attached to and rotates with the shaft, passing an electric current to a circuit via a fixed brush pressing against it.

Slip rings are usually made of Phosphor Bronze.

Slip ring motors usually have a 'phase-wound' rotor. This type of rotor has a 3-phase, double-layer, distributed winding consisting of coils used in alternators. The rotor core is made up of steel laminations which have slots to accommodate formed 3-single phase windings.