public void GravitationalAcceleration_DoubleDataReturnsCorrectValue()
{
// prereq
Approx_Works();
Scientific_Works();
// arrange
// Earth radius (meters) 6.371 x 10^6
double distance = PMath.Scientific(6.371, 6);
// kg
double massA = 68;
// Earth mass (kg) 5.97237f x 10^24
double massB = PMath.Scientific(5.97237, 24);
// m/s/s
double expected = 9.80665d;
// act
double gravity = PMath.GravitationalAcceleration(massA, massB, distance);
// assert
Assert.AreEqual(expected, gravity, "Gravitational Force: {0} != {1}", expected, gravity);
}
public void EscapeVelocity_ReturnsCorrectValue()
{
// prereq
Approx_Works();
Scientific_Works();
GravitationalAcceleration_FloatDataReturnsCorrectValue();
// arrange
// mean Earth radius (km => meters)
float distance = (float)PMath.Scientific(6.371, 6);
// typical person mass (kg)
float personMass = 70;
// Earth mass (kg)
// Ref: https://en.wikipedia.org/wiki/Earth_mass
double earthMass = PMath.Scientific(5.97237, 24);
// force is m/s/s
float force = PMath.GravitationalAcceleration(personMass, (float)earthMass, distance);
// escape velocity on earth is 11.2 km/s (km/s => m/s)
float expected = 11.2f * 1000;
// act (m/s)
double velocity = PMath.EscapeVelocity(force, distance);
// assert
Assert.IsTrue(PMath.Approx(expected, (float)velocity, 1), "Escape Velocity: expected "
+ expected + " m/s != actual " + velocity + " m/s");
}
public void GravitationalAcceleration_FloatDataReturnsCorrectValue()
{
// prereq
Approx_Works();
Scientific_Works();
// arrange
float massA = 10; // kg
float massB = 20; // kg
float distance = 5 * 1000; // km => meters
int precision = 5;
// act
float gravity = PMath.GravitationalAcceleration(massA, massB, distance);
// assert
Assert.IsTrue(PMath.Approx(0f, gravity, precision), "Gravitational Acceleration: " + TestHelper.ShowNEComparison(0f, gravity));
}
