What are the minimum energies of the two oppositely directed gamma rays in a pet procedure?

Crowbar of 5 metre is used to lift an object of 800 metre if the effort arm is 200cm calculate the force applied

Asmall object with mass 0.200 kg swings back and forth on the lower end of a light rope that is 3.00 m long. the upper end of the rope is attached to the ceiling. as the object swings through its lowest position, where the rope is vertical, the speed of the object is 5.80 m/s. at this point in the motion, what is the tension in the rope? (use g = 9.80 m/s2.)

Which of the following statements accurately describes the sign of the work done on the box by the force of the push? a. positive b. negative c. zero