a) [kg]
b)
c) F = vR,
Explanation:
a)
In this problem, we are given the rate at which the mass is expelled by the rocket:
Therefore, the total mass expelled by the rocket in a time is the given by the equation
where
is the mass expelled
R is the rate at which it is expelled
is the time interval
Here we have
R = 1300 kg/s
Therefore, substituting into the equation,
[kg]
b)
The momentum of an object is given by
where
p is the momentum
m is the mass of the object
v is the velocity of the object
In this problem, we want to find the momentum carried by the mass of the gas, , that is expelled by the rocket. This will be given by
where
is the mass of gas expelled in a time of
is the velocity of the gas
Substituting,
c)
According to Newton's second law of motion, the average force exerted on an object is equal to its rate of change of momentum:
where
F is the average force
is the change in momentum
is the time interval
In this problem, the change in momentum of the rocket is equal to the momentum of the gas expelled, so:
Substituting into the equation, we can therefore find the average force on the rocket: