PHY-102 ENERGY AND CIRCULAR MOTION
TEST PAPER 2026 STUDY GUIDE REVIEW
◉ What happens when Fnet = 0? Answer: Velocity is constant.
◉ How do you update velocity when Fnet is not zero? Answer: vf = vi
+ (Fnet/m) * deltat
◉ How do you update position? Answer: rf = ri + vi * t
◉ What is the gravitational force formula? Answer: Fg = -GMm/r^2 *
rhat
◉ What direction does the centripetal force point? Answer: Towards
the center of the circle.
◉ What is the formula for gravitational force in terms of distance?
Answer: Fgrav = ((G * m1 * m2) / (mag(r)^2)) * (-rhat)
◉ How do you find the radius of the turning circle? Answer:
Fnet_perp = mv^2/r
, ◉ What characterizes elliptical orbits? Answer: They are a 'bound
system' with negative total energy (K + U).
◉ What does a repelling system's energy graph look like? Answer: K
and U are positive, K + U is above both K and U.
◉ What happens to kinetic energy (K) at high speeds? Answer: K + U
is positive, K approaches K + U but never zero.
◉ What is escape velocity? Answer: K + U, K, & U approach 0.
◉ How do you calculate average velocity when Fnet is not zero?
Answer: vavg = (vf + vi) / 2
◉ What is the relationship between K and U in a half-bound system?
Answer: K starts positive but ends at 0, U is negative.
◉ What does the energy graph look like when speed goes to zero far
away? Answer: K, U, and K + U = 0.
◉ What is the condition for constant velocity? Answer: Fnet = 0.
◉ How is net force calculated? Answer: Fnet = deltap/deltat = m(vf -
vi)/deltat
TEST PAPER 2026 STUDY GUIDE REVIEW
◉ What happens when Fnet = 0? Answer: Velocity is constant.
◉ How do you update velocity when Fnet is not zero? Answer: vf = vi
+ (Fnet/m) * deltat
◉ How do you update position? Answer: rf = ri + vi * t
◉ What is the gravitational force formula? Answer: Fg = -GMm/r^2 *
rhat
◉ What direction does the centripetal force point? Answer: Towards
the center of the circle.
◉ What is the formula for gravitational force in terms of distance?
Answer: Fgrav = ((G * m1 * m2) / (mag(r)^2)) * (-rhat)
◉ How do you find the radius of the turning circle? Answer:
Fnet_perp = mv^2/r
, ◉ What characterizes elliptical orbits? Answer: They are a 'bound
system' with negative total energy (K + U).
◉ What does a repelling system's energy graph look like? Answer: K
and U are positive, K + U is above both K and U.
◉ What happens to kinetic energy (K) at high speeds? Answer: K + U
is positive, K approaches K + U but never zero.
◉ What is escape velocity? Answer: K + U, K, & U approach 0.
◉ How do you calculate average velocity when Fnet is not zero?
Answer: vavg = (vf + vi) / 2
◉ What is the relationship between K and U in a half-bound system?
Answer: K starts positive but ends at 0, U is negative.
◉ What does the energy graph look like when speed goes to zero far
away? Answer: K, U, and K + U = 0.
◉ What is the condition for constant velocity? Answer: Fnet = 0.
◉ How is net force calculated? Answer: Fnet = deltap/deltat = m(vf -
vi)/deltat
