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    i get so confused here....

    hre's the question, can some brain box explain why/how to do it?

    A bullet, fired vertically from a pistol, rises to a maximum height of
    1875 m above a planet in a time of 25 seconds.
    (i) Calculate the average speed of the bullet during this time.
    You are advised to show clearly how you get your answer.
    Average speed = _____________ m/s [4]
    (ii) Using your answer to part (i), or otherwise, calculate the maximum
    speed of the bullet.
    You are advised to show clearly how you get your answer.
    Maximum speed = _____________ m/s [3]
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    (i) = 1875/25 = 75
    (ii) = squar root of 2*9.8*1875
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    (Original post by WhatIsAUsername?)
    (i) = 1875/25 = 75
    (ii) = squar root of 2*9.8*1875
    Don't just post the answers. The idea is to explain it as so they can understand it :hmmm:
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    For question i) i would assume you also need to take into account from the direction of the velocity of the bullet the acceleration is
    -9.8ms^-2 due to gravity.
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    figured it out and i'm glad. the method for these questions is to wrtie:
    S
    U
    V
    A
    T

    which of thse do we know?

    S=1875
    U=0
    V=X(this is the question)
    A=unknown as bullet is fired above A PLANET, NOT EARTH SO A ISN'T known and is useless
    T=25s

    SUVT

    a) average speed=total distance/total time=1875/25= I dunno lol cba to calculate
    b)find V in other words.

    S=1/2(U+V)T

    (S/0.5)X25=V
    V= summit
 
 
 
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Updated: February 7, 2010
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