QCD and Top physics studies in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector

Beginning from 2010, ATLAS collected proton-proton collision data at a centre-of-mass energy of 7~TeV, accumulating by the Spring of 2011 an integrated luminosity of ~200 inverse picobarn. The high energy gives the possibility to produce a sizeable amount of top quarks, allowing for measurements of top quark properties and searches for heavy exotic resonances decaying to top-antitop pairs. Measurements of jet cross-sections confirm the predictions of perturbative QCD at the high energy of the Large Hadron Collider.