Question

At liftoff, a 232,000-kg Delta II space launch vehicle is accelerated
upward with a force exerted by its rocket engines. This force is called
thrust. The Delta II rocket engines produce a thrust of 3.11 million
newtons.
(a) What is the net force acting on the Delta II at liftoff?
(b) What is the acceleration of the Delta II at liftoff?
(c) Following liftoff, the acceleration of the Delta II is not constant; it
increases. Explain why this happens. (At liftoff, approximately 90%
of the weight of the Delta II is rocket fuel.)

Answer 1

@Harsha19111999

Answer 2

c'mon, dude \(\sf F = ma \rightarrow force = mass \times acceleration \)

Answer 3

(a) Net force = Thrust - Gravitational Force = Thrust - mg = 3110000-232000*9.8=836400 N

Answer 4

I got for a 8.34 X 10^5 N

Answer 5

wouldn't that be almost the same?

Answer 6

Okay

Answer 7

you have 3 significant figures so follow it

Answer 8

Yeah

Answer 9

for B, I got 3.60m/s^2

Answer 10

do you always want that other people validate your answers before you submit them? that's like cheating

Answer 11

So for (b) Acceleration = Net force / Mass = 3.60 m/sec^2

Answer 12

exactly that's what I put on my paper

Answer 13

Cool

Answer 14

And (c) Acceleration is not constant. There are many reasons

Answer 15

I rounded 3.59 to the next whole number

Answer 16

you're always asking for validation, I mean every semester

Answer 17

I kind of do, because I always see you post questions for the past year

Answer 18

1) The mass of the vehicle may decreased due to the fuel depletion 2) Thrust may increase 3) Gravity variation

Answer 19

what if let us say, these posts were to be given to your school for an evaluation, it wouldn't mean anything, yes?

Answer 20

Hey. Cool down everyone. Its not the place to quarrel

Answer 21

I am sorry @Harsha19111999

Answer 22

No problem. Have confidence in your answers and go ahead. All the best

Answer 23

thank you! I've actually did research just to figure out these problems

Answer 24

So for C you would say acceleration isn't constant

Answer 25

Yes

Answer 26

The main reason is the if you travel, fuel burns and comes out. So, the mass of fuel decreases. Acceleration is inversely proportional to Mass. So, acceleration increases