At what temperatures does the rms speed of (a) H2(molecular hydrogen) and (b) O2 (molecular oxygen) equalthe escape speed from Earth (escape speed=11.2 km/s) ? At whattemperature does the rms speed of (c) H2 and (d)O2 equal the escape speed from the Moon (where thegravitational acceleration at the surface has magnitude0.16g)? Considering the answers to parts (a) and (b), shouldthere be much (e) hydrogen and (f) oxygen high in Earth's upperatmosphere, where the temperature is about 1000 K?The answers are:(a) 1.0 × 104 K;(b) 1.6 × 105 K;(c) 4.4 × 102 K;(d) 7.0 × 103 K;(e) no;(f) yes

c)as speed changes, wavelength and frequency change.

everything changes!

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s