Question

Q.5 in image.Please answer

Answer 1

I think the answer should be B because F=ma=mv/t=1*60*1000/1=60000N

Answer 2

Answer -(5)(B) 60000N

Solution:-

v = 60km/s = 60000m/s

Also force is defined as rate of change of momentum , here mass is rate of fuel supply or M/t=1kg/s

So F = mv/t

=1 × 60000/1

=60000 N

OR

Solution:-

Overall momentum of the system is

conserved.

Therefore, change in momentum of the rocket will be equal to that of the fuel.

Change in momentum of the fuel will be

Δmν = 60000

Hence, change in momentum of the rocket

will also be:

ΔΡ = 60000

Thrust force F -

= $\frac {Δp}{Δt}$

F = 60000 N