75-Archetype SyllabusPhysics • ARCH-P-08 • Spec P3

Full 6-Card Lesson 15-Question Timed Drill

UAT-UK SPEC CODE: P3 (Mechanics)ASSUMED MATHS 1 PREREQUISITE: M4.4FREQUENCY: MEDIUM

1D Momentum Conservation, Vector Rebound Impulse (FΔt = Δp) & Collisions

Deconstructed from 10 past UAT-UK questions (4.29% of all historical Physics papers). Students using standard A-Level classroom methods spend an average of 135s on this archetype—blowing past the 90s ESAT budget. Using the 2-line Sub-90 heuristic below compresses solve time to 35s (saving 100s per question).

Historical Frequency

10 Past Qs

4.29% of Physics

Classroom Trap Time

135s

+45s over 90s budget

Sub-90 Target Time

35s

Banks +100s on the clock

Dominant UI Format

5-Option A–E

Maths 1 Skill: M4.4

Card 1 & Card 2 Preview: The Classroom Time Trap vs. Sub-90 2-Line Rule

Excerpted from our interactive 6-Step Topic Lesson for ARCH-P-08.

Launch All 6 Active-Recall Cards

CARD 1 OF 6 • THE CLASSROOM TIME TRAP (135s)

Why Students Bleed Time:

Write

p = mv = 12

and

E_k = \frac{1}{2}mv^2 = 18

. Divide

\frac{E_k}{p} = \frac{1}{2}v = \frac{18}{12} \implies v = 3\text{ m s}^{-1}

. Then

m = \frac{p}{v} = \frac{12}{3} = 4\text{ kg}

(~110s).

In 10 past UAT-UK questions (4.29% of Physics), candidates lose 100s by failing to assign opposite signs to approaching (+u) and rebounding (-v) velocities. Instead, apply P3 with Maths 1 skill M4.4.

CARD 2 OF 6 • THE 2-LINE SUB-90 HEURISTIC (<35s)

Line 1 (Momentum-Energy Identity): Memorise

E_k = \frac{p^2}{2m} \iff m = \frac{p^2}{2E_k}

Line 2 (Substitute):

m = \frac{12^2}{2 \times 18} = \frac{144}{36} = 4\text{ kg}

(20s).

Sanity & Limit Check: Verify units/signs against sign_or_direction_flip (Calculating rebound momentum change as m(v - u) instead of m(v - (-u)) = m(v + u)) and subsystem_isolation_trap (Dividing total momentum by m₁ instead of coalesced mass (m₁ + m₂) after an inelastic collision).

Examiner Distractor Blueprint for ARCH-P-08

FOIL #1sign_or_direction_flip

Calculating rebound momentum change as m(v - u) instead of m(v - (-u)) = m(v + u)

Failing to assign opposite signs to approaching (+u) and rebounding (-v) velocities.

Open Sign / Direction Flip Clinic

FOIL #2subsystem_isolation_trap

Dividing total momentum by m₁ instead of coalesced mass (m₁ + m₂) after an inelastic collision

Forgetting that stuck-together trolleys move with combined mass m₁ + m₂.

Open Subsystem Isolation Trap Clinic

FOIL #3sign_or_direction_flip

Adding instead of subtracting initial momenta m₁*u₁ + m₂*u₂ when trolleys move towards each other

Treating momentum as a scalar rather than a signed 1D vector.

Open Sign / Direction Flip Clinic

FOIL #4intermediate_stop_trap

Outputting final velocity v instead of kinetic energy lost E_k_initial - E_k_final

Stopping after the momentum step when the question asks for dissipated kinetic energy.

Open Intermediate Stop Trap Clinic

Try 1 Live Sample Question Under the 90-Second Stopwatch

Press W to open the 2-line dry-wipe scratchpad, select A–E, and lock in to reveal the Dual-View solution.

Full 6-Card Lesson Launch All 15 Questions (ARCH-P-08)

ARCH-P-08: 1D Momentum Conservation, Vector Rebound Impulse (FΔt = Δp) & Collisions (Sample)Physics

00:00.0

SUB-90 ZONE (<35S)

0.0s35s Sub-9090s ESAT Budget150s Classroom

Question 1 of 1ARCH-P-08 (6-Card Lesson)Format: Standard 5-Option

Right-click any option to cross out • Keys A–E + Enter

Question 1 of 1 • 90s Target

Ready to Start Question 1?

The question stem, diagram, and answer options are hidden behind this pre-start gate. When you click below, the question will reveal and your 90-second split stopwatch will immediately begin ticking.

Physics•ARCH-P-08•Standard 5-Option

or press Enter to start