a) To find the rocket's thrust, we can use the formula thrust = (mass flow rate) * (exhaust velocity). We are given the mass flow rate (480 kg/s) and the exhaust velocity (3.27 km/s). We need to convert the exhaust velocity to the SI unit, meters per second.
3.27 km/s = 3270 m/s
Thrust = (480 kg/s) * (3270 m/s) = 1,569,600 N
b) To find the mass of the rocket after the 250 s firing, we can subtract the mass of fuel consumed from the initial mass. We know the initial mass of the rocket (2.55 x 10^5 kg), the initial mass of fuel (1.81 x 10^5 kg), and the fuel consumption rate (480 kg/s). We can calculate the mass of fuel consumed during the 250 s firing:
Fuel consumed = (480 kg/s) * (250 s) = 1.20 x 10^5 kg
The mass of the rocket after the firing is the initial mass minus the mass of fuel consumed:
Remaining mass = (2.55 x 10^5 kg) - (1.20 x 10^5 kg) = 1.35 x 10^5 kg
c) As per the third equation in the initial answer, we can find the speed of the rocket after the 250 s firing.
Speed of the rocket = (Thrust * Timeburn) / Avgmassrocket
The initial mass of the rocket is 2.55 x 10^5 kg, and the mass of fuel consumed during the firing is 1.20 x 10^5 kg. So, the average mass of the rocket during the firing is:
Avgmassrocket = (Initial mass + Remaining mass) / 2 = (2.55 x 10^5 kg + 1.35 x 10^5 kg) / 2 = 1.95 x 10^5 kg
Now, we can calculate the speed of the rocket after the firing:
Speed of rocket = (1,569,600 N * 250 s) / (1.95 x 10^5 kg) = 2010 m/s
A rocket whish is in deep space and initially at rest relative to an inertial reference frame, has a mass of 2.55 X 10^5 kg of which 1.81 X10^5 kg is fuel. The rocket engine is then fired for 250 s during which feul is consumed at the rate of 480 kg/s. The speed of the exhaust products relative toe the rock is 3.27 km/s. a) what is the rocket’s thrust? B) After the 250s firing what is the mass c) the speed of the rocket after the 250s firing?
a) I would multiply 1.81x10^5*480
b) Would I used the answer from a) and divide by acceleration?
c)i am not sure what to do for this part
Thrust=mv/t= m/t *v You are given the fuel burn rate (m/t) and v.
massleft= intial mass - fuelburnrate*time
Speed of rocket= thrust*timeburn/avgmassrocket
where average mass of rocket= starting mass -fuelburned/2
1 answer
0 answers