Find the fractional decrease of kinetic energy of a of mass m when a head on elastic collision takes place with another particle of mass m2 initially at rest. in this context show why hydrogen would be best to be used for slowing down. actually d20, not h, o is used. why?

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.

The mass of the sun is 1.99×1030kg and its distance to the earth is 1.50×1011m. what is the gravitational force of the sun on the earth?

Acertain radio station broadcasts radio waves that have a wavelength of 298cm what is its broadcast frequency?