Easy -1.2 This is a straightforward one-step SUVAT problem requiring only the application of v² = u² + 2as with given values. It's a standard textbook exercise with no problem-solving insight needed, making it easier than average for A-level mechanics.
1 A pellet is fired vertically upwards at a speed of \(11 \mathrm {~ms} ^ { - 1 }\). Assuming that air resistance may be neglected, calculate the speed at which the pellet hits a ceiling 2.4 m above its point of projection.
Use of \(v^2 = u^2 + 2as\) or complete sequence of correct suvat. Accept sign errors in substitution.
\(v = 8.6\) so \(8.6 \text{ m s}^{-1}\)
A1
All correct
A1
cao [Award all marks if 8.6 seen WWW] Do not condone \(\pm 8.6\).
$v^2 = 11^2 + 2 \times (-9.8) \times 2.4$ | M1 | Use of $v^2 = u^2 + 2as$ or complete sequence of correct suvat. Accept sign errors in substitution.
$v = 8.6$ so $8.6 \text{ m s}^{-1}$ | A1 | All correct
| A1 | cao [Award all marks if 8.6 seen WWW] Do not condone $\pm 8.6$.
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1 A pellet is fired vertically upwards at a speed of $11 \mathrm {~ms} ^ { - 1 }$. Assuming that air resistance may be neglected, calculate the speed at which the pellet hits a ceiling 2.4 m above its point of projection.
\hfill \mbox{\textit{OCR MEI M1 2011 Q1 [3]}}