For those going on to A levels after your Os
And also for those going from J1 to J2
This is an extremely common H2 physics questions on Dynamics
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An 18-g rifle bullet travelling 230 m/s buries itself in a
3.6-kg pendulum hanging on a 2.8-m-long string, which makes the
pendulum swing upward in an arc. Determine the horizontal component
of the pendulum's displacement.
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Hint: You need both Principle of conservation of momentum and
Principle of conservation of energy to solve this question.
Attempt before looking at the answer here