MCAT Physics 2

Question 1

A 2 kg block slides down a frictionless incline of 30°. What is the block's acceleration along the incline?

Accepted Answer

4.9 m/s²

Answer

Acceleration along a frictionless incline is g·sin(θ) = 9.8 × sin(30°) = 9.8 × 0.5 = 4.9 m/s².

Question 2

A spring with spring constant k = 200 N/m is compressed by 0.1 m. How much potential energy is stored?

Accepted Answer

1 J

Answer

Elastic potential energy = ½kx² = ½ × 200 × (0.1)² = 1 J.

Question 3

Which of the following best describes the Doppler effect when a sound source moves toward a stationary observer?

Accepted Answer

Observed frequency is higher than emitted frequency

Answer

When a source moves toward an observer, sound wavefronts bunch together, shortening wavelength and increasing observed frequency.

Question 4

A fluid flows through a pipe that narrows from a cross-sectional area of 0.04 m² to 0.01 m². If the fluid velocity in the wide section is 2 m/s, what is the velocity in the narrow section?

Accepted Answer

8 m/s

Answer

By continuity, A₁v₁ = A₂v₂, so v₂ = (0.04 × 2) / 0.01 = 8 m/s.

Question 5

Two point charges of +2 μC and −2 μC are separated by 0.1 m. What is the direction of the electrostatic force on the positive charge?

Accepted Answer

Toward the negative charge

Answer

Opposite charges attract, so the positive charge experiences a force directed toward the negative charge.

MCAT - Medical College Admission Test Practice Test

MCAT - Medical College Admission Test Practice Test

MCAT Physics 2