Moderate -0.5 This is a straightforward application of the impulse-momentum theorem with constant force. Students need to apply F×t = m(v-u) with all values given directly, requiring only algebraic rearrangement to find m. While it involves mechanics rather than pure maths, it's a standard single-step problem with no conceptual challenges beyond recalling the basic formula.
1 A bullet of mass \(m \mathrm {~kg}\) is fired horizontally into a fixed vertical block of material. It enters the block horizontally with speed \(250 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) and emerges horizontally with speed \(70 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) after 0.04 s . The block offers a constant horizontal resisting force of magnitude 450 N . Find the value of \(m\).
1 A bullet of mass $m \mathrm {~kg}$ is fired horizontally into a fixed vertical block of material. It enters the block horizontally with speed $250 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ and emerges horizontally with speed $70 \mathrm {~m} \mathrm {~s} ^ { - 1 }$ after 0.04 s . The block offers a constant horizontal resisting force of magnitude 450 N . Find the value of $m$.\\
\hfill \mbox{\textit{CAIE FP2 2018 Q1 [3]}}