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Physics question? (suvat) UKCAT Watch

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    Explain to me how is accelerating from rest to 60mph in 6s is equivalent to moving at 30mph for 6s????

    The QR on the UKCAT mock 1 is unbelievably hard!!
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    (Original post by bobwibbles)
    Explain to me how is accelerating from rest to 60mph in 6s is equivalent to moving at 30mph for 6s????

    The QR on the UKCAT mock 1 is unbelievably hard!!
    If you draw a graph of speed versus time for accelerating from rest to 60mph in 6s, you would get a straight line pass through the origin to 60 mph. The area under this graph is the distance travelled by the object in 6 s.

    It is found by calculating the area of a triangle:

     \frac{1}{2} \times 60 \text{ mph} \times 6 \text{ s}

    Before computing the whole thing do a bit of simplification,

     \frac{1}{2} \times 60 \text{ mph} \times 6 \text{ s} = 30 \text{ mph} \times 6 \text{ s}

    Actually, 30 mph is the average speed for the journey of accelerating from rest to 60mph in 6s.
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    (Original post by Eimmanuel)
    If you draw a graph of speed versus time for accelerating from rest to 60mph in 6s, you would get a straight line pass through the origin to 60 mph. The area under this graph is the distance travelled by the object in 6 s.

    It is found by calculating the area of a triangle:

     \frac{1}{2} \times 60 \text{ mph} \times 6 \text{ s}

    Before computing the whole thing do a bit of simplification,

     \frac{1}{2} \times 60 \text{ mph} \times 6 \text{ s} = 30 \text{ mph} \times 6 \text{ s}

    Actually, 30 mph is the average speed for the journey of accelerating from rest to 60mph in 6s.
    Ah makes sense. Thank you!
 
 
 
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