The strikes destroyed three IS trucks and destroyed a mortar position near the Mosul Dam, Xinhua quoted a statement by US Army's Central Command as saying.
The operation was conducted under authority to protect US personnel and facilities, support humanitarian efforts, and support Iraqi forces that are acting in furtherance of these objectives, the statement said.
US Central Command has conducted a total of 123 airstrikes across Iraq.
The White House on Monday said that its latest round of airstrikes in Iraq are "consistent" with prior military missions the White House has authorised to date in Iraq.
Meanwhile, US President Barack Obama said he had authorised armed forces to conduct targeted air strikes in support of an operation to deliver humanitarian assistance to the town of Amerli, where thousands of Shia Turkomen have been cut off from receiving food and medical supplies for two months by the IS militants.
Obama also noted that the US Air Force delivered aid to the town, alongside aircraft from Australia, France and Britain, which also dropped supplies.
These operations are limited in their nature, duration, and scope and are being undertaken in coordination with and at the request of Iraq's government, the president added.
The US president first authorised limited air strikes on IS targets on Aug 7, as the group seized more cities and towns in its advance on Erbil, capital of Iraq's autonomous Kurdish region, and trapped many civilians including the minority Yazidis on Mount Sinjar.