A 20,000 kg rocket has a rocket motor that generates 3.2 ✕ 105 N of thrust.
(a) What is the rocket's initial upward acceleration?
Incorrect: Your answer is incorrect. m/s2

(b) At an altitude of 5000 m the rocket's acceleration has increased to 7.9 m/s2. What mass of fuel has it burned?

Question

A 20,000 kg rocket has a rocket motor that generates 3.2 ✕ 105 N of thrust.
(a) What is the rocket's initial upward acceleration?
Incorrect: Your answer is incorrect. m/s2

(b) At an altitude of 5000 m the rocket's acceleration has increased to 7.9 m/s2. What mass of fuel has it burned?

anonymous · Answer

well F=ma so solve for a

anonymous · Answer

not so sure about the second part tho haha.

anonymous · Answer

well we know x initial is 0m 
x final is 5000m
velocity initial is 0 m/s
final velocity = ?
acceleration = the answer you got on the first question + 7.9 m/s^2

anonymous · Answer

or, if they assume the rocket's thurst is constant, we can just do F=ma again and solve for m

anonymous · Answer

That was what I thought for the first part but that comes back as a wrong answer

anonymous · Answer

oh really?

anonymous · Answer

maybe it has to do something with work then.

anonymous · Answer

not sure. sorry :l

anonymous · Answer

maybe try a negative lol