Electing to bat, India rode on half-centuries from Prithvi Shaw, Manjot Kalra and Shubman Gill to post a formidable total of 328/7 in their 50 overs.
Indian pacers Shivam Mavi and Kamlesh Nagarkoti then picked up three wickets each as the Australians were dismissed for 228 in 42.5 overs. Nagarkoti picked up 3/29, while Mavi finished with 3/45.
The Indian pace trio of Mavi, Nagarkoti and Ishan Porel clocked over 145 km per hour during their spells. An injury to Porel was the only cause of concern for the Indians.
An excellent all-round performance by Jack Edwards was the only bright spark for Australia on the day.
Edwards returned figures of 4/65 with his right-arm medium pace and was the only Australian who stood up to the Indian bowlers, posting a 90-ball 73 before being bowled by left-arm spinner Anukul Roy.
The Indians dominated proceedings from the moment skipper Shaw won the toss.
Shaw led from ther front, scoring 94 runs in a 100-ball innings which contained eight boundaries and a couple of sixes.
He did, however, go through a moment of anxiety when he was caught behind off Will Sutherland's bowling. But television replays revealed that Sutherland had overstepped.
Shaw received a second reprieve, again off Sutherland's bowling, when he mistimed a pull only to be caught at deep backward square.
The Indian captain was, however, dismissed off the very next ball when he was caught by Baxter Holt on the off-side.
Fellow opener Manjot Kalra gave his skipper excellent support from the other end with a 99-ball 86 which included 12 boundaries and a six.
They put together an opening stand of 180 runs to gift a strong foundation to the Indian innings.
This was the highest opening partnership for India in any U19 World Cup and their second highest for any wicket.
Shubman Gill then hammered home the advantage with 63 runs off 54 balls with six boundaries and a six.
Abhishek Sharma provided a late flourish to the Indian innings with an 8-ball 23.
Except for Edwards, the rest of the the Australian bowlers had a forgettable day although off-spinner Param Uppal was economical over his eight overs with figures of 1/35.
The Indian total was the highest ever by any team against Australia in an U19 World Cup.
In reply, Australia were given a steady start as Edwards and Max Bryant produced an opening stand of 57 runs in 14 overs before the latter was caught at extra cover off Nagarkoti's bowling.
The former champions then lost wickets at regular intervals as the Indian bowlers started to dominate.
In other matches on the day, Sri Lanka coasted to a convincing seven-wicket win over Ireland in Group D with opener Dhananjaya Lakshan slamming a fine unbeaten 101 from 120 deliveries with the help of eight fours and a six.
Chasing 208 for victory, Sri Lanka had lost two early wickets after a double-strike from Aaron Cowley and were struggling at 51/3 one stage.
However, Lakshan's unbroken 157-run partnership with captain Kamindu Mendis, who remained unbeaten on 74, took the team through.
Earlier, Mendis had also grabbed 3/35 with his spin bowling to restrict Ireland to 206/8 in the 48-over match after openers Jamie Grassi (75) and Mark Donegan (36) had provided the Irish a 73-run opening stand.
In Group A, South Africa piled on a massive 341/7 after electing to bat first.
This was South Africa's second highest total in the U19 World Cup. Their previous highest was 359/6 against Namibia in 2012.
South Africa captain Raynard van Tonder slammed a stroke-filled 143 off 121 balls, smashing 14 fours and five sixes.
He was involved in a 125-run second-wicket stand with left-handed opener Jiveshan as the Proteas virtually batted the opposition out of the contest.
Pillay scored 62 runs off 67 balls with seven fours and a six.
Kenya were never in the chase and eventually finished at 172/7 in 50 overs. They had been reduced to 50/4 in the 19th over and then 98/6 in the 34th.
Brief scores:
India: 328/7 in 50 overs (Shaw 94, Kajra 86, Gill 63; Edwards 4/65) vs Australia: 228 in 42.5 overs (Edwards 73; Savi 3/45 Nagrakoti 3/29).
Ireland: 207/8 in 48 overs (Jamie Grassi 75; Kamindu Mendis 3/35) vs Sri Lanka: 208/3 in 37.3 overs (Dhananjaya Lakshan 101 not out, Kamindu Mendis 74 not out).
South Africa: 341/7 in 50 Overs (Raynard van Tonder 143, Jiveshan Pillay 62) vs Kenya: 172/7 in 50 Overs (Jasraj Kundi 41, Ankit Hirani 35 not out).
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
