Think about a construction crane moving a steel beam. Where does the energy used to complete the task come from? What evidence do you have that the amount of energy involved in the crane example is different from that in the wind-up toy example?

What element breaks down into yttrium-90?

Acurium-245 nucleus is hit with a neutron and changes as shown by the equation. complete the equation by filling in the missing parts. 52

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?