PHY 101 Mock Test 1

Displacement has both magnitude (distance) and direction. Temperature, mass, and time are scalars with magnitude only.

This is the Law of Conservation of Linear Momentum: If ΣF_ext = 0, then ΔP_total = 0.

By definition, P_total = Σ (m_i * v_i) for all particles i.

The force on the bullet forward is paired with an equal and opposite force on the gun backward, causing recoil. It also illustrates conservation of momentum.

It does not exchange matter or energy with its surroundings.
Explanation: An isolated system has no interactions across its boundary, no transfer of mass, heat, or work.

This is the operational definition: a frame where an object with no net force acting on it moves with constant velocity (or remains at rest).

Multiplying by a negative scalar (-2) scales the magnitude by 2 and reverses the direction by 180 degrees.

Just as mass resists linear acceleration (F=ma), the moment of inertia (I) resists angular acceleration (τ=Iα).

An event is a fundamental concept defined by its spatial coordinates (x, y, z) and its time coordinate (t).

With no horizontal force, the horizontal component of velocity remains unchanged. The vertical acceleration is always -g downward.

By definition, the normal force is the component of contact force perpendicular (normal) to the surface. Its magnitude depends on the situation.

Rotational KE = (1/2)Iω². KE is proportional to ω², so doubling ω increases KE by a factor of 2² = 4.

This is a key consequence of Einstein’s theory of special relativity. Simultaneity is not absolute but depends on the observer’s state of motion.

α = dω/dt, analogous to linear acceleration a = dv/dt.

A fundamental principle is that all terms in a valid physical equation must have the same dimensions. Dimensional analysis verifies this consistency but cannot determine dimensionless constants.

These mathematical functions are defined as power series. Adding quantities with units like meters or seconds inside them is physically meaningless; the argument must be a pure number.

A · B = |A||B|cosθ. For θ = 90°, cos90° = 0, so the dot product is zero.

This principle asserts that the fundamental laws of motion are invariant (take the same form) for all observers moving with constant velocity relative to each other.

This is a common point of confusion. The two forces are an interaction pair between two different bodies, so they do not cancel for a single body.

Impulse, J = ∫ F dt (or F_avg Δt for constant force), is a measure of the change in momentum it produces.