UPCAT Physics Reviewer 2026

Answer: C. 1st: ketchup+hammering; 2nd: pushing+dropping; 3rd: billiards+rocket

1st Law (inertia): ketchup dislodging and tightening hammerhead (sudden stop/inertia). 2nd Law (F=ma): pushing heavy object and dropping a ball. 3rd Law (action-reaction): colliding billiard balls and rocket launching.

Answer: B. Energy from heat source transferred to gas, which pushes piston upward.

Correct thermodynamic sequence: heat source → thermal energy added to gas → gas expands → pushes piston upward. This is the basis of heat engines.

Answer: A. I only

Bulbs in series (Circuit I) give the highest equivalent resistance (R_total = R + R + R = 3R). Parallel circuits reduce equivalent resistance.

Answer: A. 2 m/s²

Step 1: Identify the forces acting on the box from the force diagram: applied force of 50N in the direction of motion and friction force of 10N opposing the motion. Step 2: Calculate the net force using $\sum F = F_{applied} - F_{friction} = 50N - 10N = 40N$. Step 3: Apply Newton's second law, $F = ma$, where the mass is 20 kg: $40N = (20 kg)(a)$. Step 4: Solve for acceleration: $a = \frac{40N}{20 kg} = 2 m/s²$ in the direction of the applied force. Therefore, the acceleration of the box is 2 m/s².

Answer: A. 0.0 N

An object at rest has zero acceleration, so by Newton's 2nd Law (F_net = ma), the net force must be zero.

Answer: A. Parallel circuit (bulbs in parallel branches)

Step 1: In a parallel circuit, each bulb is connected on its own separate branch, providing an independent path from the power source through each bulb and back to the source. Step 2: When bulbs are arranged in parallel, the failure of one bulb does not affect the operation of the others, since each bulb has its own complete circuit path. Step 3: If bulb 2 or bulb 3 burns out (creating an open circuit in their respective branches), bulb 1 continues to operate normally because its circuit path remains intact and unaffected. Step 4: In contrast, a series circuit would cause all bulbs to go out if any single bulb fails, since there is only one path for current flow. Therefore, the parallel circuit arrangement is the correct answer.

Answer: A. Student 1

Student 1 has similar precision (±0.25 vs ±0.20). Students 2-4 have much larger uncertainty (±11.5), making them far less consistent with Keech's precise measurement. "Most consistent" refers to similar uncertainty/precision.

Answer: B. 100

A's time = 3000/600 = 5 hours. In 5 hours, B covers 580 × 5 = 2900 miles. Miles remaining for B = 3000 - 2900 = 100 miles.

Answer: D. Student B did twice as much work climbing the tower.

GPE = mgh. Student B (2m) × g × h = twice the GPE of student A (m × g × h). Work done climbing equals GPE gained, so B did twice the work. Both reach the water at the same time (gravity affects all objects equally). KE at bottom = GPE, so B also has twice the KE.

Answer: D. E is radiation and F is convection.

Position E (at the heating element): radiation (electromagnetic waves emitted). Position F (around the heater): convection (hot air rises and circulates). This is the typical heat distribution pattern of a radiation heater.

Answer: A. All three will run out at the same time.

In a series circuit, the same current flows through all components. Identical batteries in series discharge at the same rate and run out simultaneously.

Answer: B. has the same magnitude as the total force which resists the motion of the cabinet.

Constant velocity means zero acceleration (Newton's 1st Law). For zero acceleration, net force = 0, meaning the applied force equals the opposing frictional force in magnitude.