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    If I have to find out the average velocity of a rocket's descent
    (I have: Final velocity and time and acceleration)
    Would I let the initial velocity equal 0 as at maximum height it turns around and velocity = 0 or would I find it out using SUVAT?
    I used suvat but it is wrong lol so i'm guessing use initial velocity as 0

     Average velocity = Initial velocity+Final velocity/2

Final velocity = 175 m/s

Initial velocity = u=v-at → u=175-(9.8*360) = -3353

Average velocity = -3353+175/2 = -1589m/s
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    (Original post by AdeptDz)
    If I have to find out the average velocity of a rocket's descent
    (I have: Final velocity and time and acceleration)
    Would I let the initial velocity equal 0 as at maximum height it turns around and velocity = 0 or would I find it out using SUVAT?
    I used suvat but it is wrong lol so i'm guessing use initial velocity as 0

     Average velocity = Initial velocity+Final velocity/2

Final velocity = 175 m/s

Initial velocity = u=v-at → u=175-(9.8*360) = -3353

Average velocity = -3353+175/2 = -1589m/s
    can you please provide all the information given in the question if possible? I think I can help but I just need the whole question if that's okay
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    (Original post by sue99)
    can you please provide all the information given in the question if possible? I think I can help but I just need the whole question if that's okay
    assessment of the rocket’s descent

    

Mass of the Rocket = 1500kg

Duration of landing impact = 0.04 s

Velocity at time of impact = 175 m/s

Distance travelled = 30km

Time taken to complete journey = 6 minutes

Acceleration due to gravity = 9.8 m/s^2

    Average velocity of the rocket’s journey (m/s) ?
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    (Original post by AdeptDz)
    assessment of the rocket’s descent

    

Mass of the Rocket = 1500kg

Duration of landing impact = 0.04 s

Velocity at time of impact = 175 m/s

Distance travelled = 30km

Time taken to complete journey = 6 minutes

Acceleration due to gravity = 9.8 m/s^2

    Average velocity of the rocket’s journey (m/s) ?
    Hi,
    I cannot say I fully understand the given problem.

    I hope you understand the difference between average speed and average velocity.

    Based on the data, it is not clear whether the journey of the rocket has a part that goes up and another part that comes down such that the distance travelled is 30 km or the 30 km is just meant for descending part.

    If the 30 km is just for the descending part, then average velocity can be found by
     v_{ave}= \frac{\text{total displacement}}{\text{total time taken}}

     v_{ave} = \frac{30 000}{6 \times 60 }

    assuming that the distance travelled is equal to the total displacement.

    But if the 30 km has an ascending journey and a descending journey, then the total displacement is most likely to be zero (because it is back to the origin by assumption, as there is no further data to deduce otherwise).
    So the average velocity is zero.
 
 
 
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