What will be the

According to 10% law, only 10% of energy entering a particular trophic level of organisms is available for transfer to the next higher trophic level.

Energy available to 1^st Trophic level = 10,000J

1 % of this energy = 100J

So, First Trophic level has energy = 100J

Energy to 2^nd Trophic level = 10% of 100 = 10 Joules