NJIT PHYSICS 203 EARTH IN SPACE PRACTICE
EXAMINATION 2026 QUESTIONS WITH ANSWERS GRADED
A+
● Newton's Laws of Motion. Answer: Three fundamental laws describing force mass and
motion
● First Law of Motion. Answer: Object remains at rest or constant velocity unless acted on
by net force
● Second Law of Motion. Answer: Net force equals mass times acceleration F equals ma
● Third Law of Motion. Answer: Every action has an equal and opposite reaction
● Inertia. Answer: Tendency of an object to resist changes in its motion
● Momentum. Answer: Product of mass and velocity p equals mv
● Conservation of Momentum. Answer: Total momentum of an isolated system remains
constant
● Angular Momentum. Answer: Rotational analog of linear momentum L equals Iω
● Conservation of Angular Momentum. Answer: Total angular momentum of an isolated
system is constant explaining orbital mechanics
● Torque. Answer: Rotational force causing angular acceleration
● Centripetal Acceleration. Answer: Inward acceleration of an object moving in a circle v
squared over r
● Centripetal Force. Answer: Net inward force required to maintain circular motion
● Gravity. Answer: Attractive force between all objects with mass
● Gravitational Potential Energy. Answer: Energy stored due to position in a gravitational
field
● Kinetic Energy. Answer: Energy of motion equal to one half mass times velocity squared
, ● Work-Energy Theorem. Answer: Net work done on an object equals its change in kinetic
energy
● Conservation of Energy. Answer: Total mechanical energy is constant in the absence of
non-conservative forces
● Escape Velocity. Answer: Minimum speed needed to escape a gravitational field equal to
root two GM over r
● Circular Orbit. Answer: Orbit where centripetal force equals gravitational force
● Geosynchronous Orbit. Answer: Orbit where orbital period matches Earth's rotation
period
● Geostationary Orbit. Answer: Geosynchronous orbit directly above the equator appearing
stationary from Earth
● Lagrange Points. Answer: Five locations in a two-body system where a small object can
remain stationary
● Vis-Viva Equation. Answer: Orbital mechanics equation relating orbital speed to position in
an ellipse
● Reduced Mass. Answer: Effective mass used in two-body gravitational problems
● Center of Mass. Answer: Point where the entire mass of a system can be considered to act
● Tidal Locking. Answer: Situation where rotation period equals orbital period due to tidal
friction
● Tidal Friction. Answer: Dissipation of tidal energy causing orbital changes over time
● Roche Limit. Answer: Distance inside which tidal forces overcome the self-gravity of a
small body
● Hill Sphere. Answer: Region around a body where its gravity dominates over the central
body's tidal force
● Orbital Energy. Answer: Sum of kinetic and gravitational potential energy of an orbiting
body
● Virial Theorem. Answer: Relation between average kinetic and potential energy for a
gravitationally bound system
EXAMINATION 2026 QUESTIONS WITH ANSWERS GRADED
A+
● Newton's Laws of Motion. Answer: Three fundamental laws describing force mass and
motion
● First Law of Motion. Answer: Object remains at rest or constant velocity unless acted on
by net force
● Second Law of Motion. Answer: Net force equals mass times acceleration F equals ma
● Third Law of Motion. Answer: Every action has an equal and opposite reaction
● Inertia. Answer: Tendency of an object to resist changes in its motion
● Momentum. Answer: Product of mass and velocity p equals mv
● Conservation of Momentum. Answer: Total momentum of an isolated system remains
constant
● Angular Momentum. Answer: Rotational analog of linear momentum L equals Iω
● Conservation of Angular Momentum. Answer: Total angular momentum of an isolated
system is constant explaining orbital mechanics
● Torque. Answer: Rotational force causing angular acceleration
● Centripetal Acceleration. Answer: Inward acceleration of an object moving in a circle v
squared over r
● Centripetal Force. Answer: Net inward force required to maintain circular motion
● Gravity. Answer: Attractive force between all objects with mass
● Gravitational Potential Energy. Answer: Energy stored due to position in a gravitational
field
● Kinetic Energy. Answer: Energy of motion equal to one half mass times velocity squared
, ● Work-Energy Theorem. Answer: Net work done on an object equals its change in kinetic
energy
● Conservation of Energy. Answer: Total mechanical energy is constant in the absence of
non-conservative forces
● Escape Velocity. Answer: Minimum speed needed to escape a gravitational field equal to
root two GM over r
● Circular Orbit. Answer: Orbit where centripetal force equals gravitational force
● Geosynchronous Orbit. Answer: Orbit where orbital period matches Earth's rotation
period
● Geostationary Orbit. Answer: Geosynchronous orbit directly above the equator appearing
stationary from Earth
● Lagrange Points. Answer: Five locations in a two-body system where a small object can
remain stationary
● Vis-Viva Equation. Answer: Orbital mechanics equation relating orbital speed to position in
an ellipse
● Reduced Mass. Answer: Effective mass used in two-body gravitational problems
● Center of Mass. Answer: Point where the entire mass of a system can be considered to act
● Tidal Locking. Answer: Situation where rotation period equals orbital period due to tidal
friction
● Tidal Friction. Answer: Dissipation of tidal energy causing orbital changes over time
● Roche Limit. Answer: Distance inside which tidal forces overcome the self-gravity of a
small body
● Hill Sphere. Answer: Region around a body where its gravity dominates over the central
body's tidal force
● Orbital Energy. Answer: Sum of kinetic and gravitational potential energy of an orbiting
body
● Virial Theorem. Answer: Relation between average kinetic and potential energy for a
gravitationally bound system
