Calculate the force exerted on a rocket given that the propelling gases are expelled at a rate of 1500 kg/s with a speed of 4.0x10^4 (at the moment of take off)

we know that momentum is given as

P = mv

where P = momentum , m = mass , v = velocity

taking derivative both side relative to "t"

dP/dt = v (dm/dt)

we know that :  dP/dt  = F = force

hence

F = v (dm/dt)

given that :

dm/dt = rate of mass expelled = 1500 kg/s

v = velocity = 4 x 10⁴ m/s

hence  , inserting the values in the above formula

F = (4 x 10⁴) (1500)

F = 6 x 10⁷ N

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.

electrical potential energy =0.072 j

explanation:

electrical potential energy is given by

u= q δv

q= charge=6 c

δv= potential difference and is given by

δv= e d

e= electric field

d= distance=5 mm=0.005 m

δv=2.4 (0.005)=0.012 v

now electric potential energy= u= q δv

u=6 (0.012)

u=0.072 j