4p A teacher pushed a 98 N desk across a floor for a distance of 5 m he
exerted a horizontal force of 20 N for four seconds. 1) How much work
was done ? 2) How was his power ? 3) what is meant by energy = 3J*

If 21.2 kcals of energy is released by this reaction, how many kj does the reaction release? (1 cal 4.184 j)

Acyclotron is used to produce a beam of high-energy deuterons that then collide with a target to produce radioactive isotopes for a medical procedure. deuterons are nuclei of deuterium, an isotope of hydrogen, consisting of one neutron and one proton, with total mass 3.34×10−27kg. the deuterons exit the cyclotron with a kinetic energy of 6.40 mev .a-what is the speed of the deuterons when they exit? b-if the magnetic field inside the cyclotron is 1.25 t, what is the diameter of the deuterons' largest orbit, just before they exit? c-if the beam current is 350 μa how many deuterons strike the target each second?

The inverse square law applies to: intensity of sound gravitational force intensity of light electric force magnetic force