A 40 kg boy standing initially motionless on frictionless ice throws a 2.2 kg rock away from himself at a speed of 5.1 ". What is tre boy's speed after he throws the rock?
m
boy
*Be sure to enter the absolute value of your answer. Also, round your answer to the nearest hundredth if necessary.

** urgent** the voltage across the primary winding is 350,000 v, and the voltage across the secondary winding is 17,500 v. if the secondary winding has 600 coils, how many coils are in the primary winding? a- 30 coilsb- 583 coilsc- 12,000 coilsd- 332,500 coils

It is really hard for me right know

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.