The Uniform Acceleration Equations · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Two equations for steady speeding

Science · Forces & Motion · ages 14-16
Name ______________________   Date ____________

  1. A car goes from 0 to 20 metres per second in 10 seconds, speeding up steadily. What is its acceleration in metres per second squared?

    Answer: ______________

  2. When should you use v equals u plus a t?

    • Only when the object is falling
    • When acceleration keeps changing wildly
    • When acceleration is steady and time is known

  3. Which equation should you reach for when time is missing but distance is known?

    • v squared = u squared + 2as
    • v = u + at
    • t = (v - u) / a

  4. Forward counts as positive. A car brakes to slow down. What is the sign of its acceleration?

    • Positive, since braking adds speed
    • Negative, since speed falls as time passes
    • Always zero

  5. A car starts from rest and accelerates at 2 metres per second squared for 10 seconds. What is its final velocity in metres per second?

    Answer: ______________

  6. A question gives u, a and s but not t, and asks for v. Which equation fits?

    • v = u + at
    • v squared = u squared + 2as
    • Give up, since no equation fits

  7. A ball is thrown straight up. While it still rises, what is the sign of its acceleration?

    • Steadily positive, since it still moves up
    • Zero, since gravity pauses mid-flight
    • Negative, since gravity pulls back down

  8. An object starts from rest with acceleration 2 metres per second squared over a distance of 25 metres. What is its final velocity in metres per second?

    Answer: ______________

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Two equations for steady speeding W1-mt_yJMJQ8_KqR-s1

  1. 2 · Speed change over time: 20 divided by 10 is 2.
  2. When acceleration is steady and time is known · That equation links the four quantities with time in them.
  3. v squared = u squared + 2as · The second equation links speeds, acceleration and distance with no t.
  4. Negative, since speed falls as time passes · Braking shrinks forward speed, so acceleration points backward.
  5. 20 · v is 0 plus 2 times 10, which is 20.
  6. v squared = u squared + 2as · If time is missing from your list, reach for the second equation.
  7. Negative, since gravity pulls back down · Gravity drags downward the whole flight, even on the way up.
  8. 10 · v squared is 0 plus 2 times 2 times 25, which is 100, so v is 10.
Worksheet · LightMySky