Equal to 0
According to Newton’s First Law, this quantity is equal to zero for an object moving at a constant velocity
What is force? (or acceleration)
This mysterious theoretical substance is believed to be causing the universe to expand at an increasing rate
What is dark energy?
Copernicus proposed a heliocentric model where planets orbit the Sun in concentric circles. Later, Kepler improved this model by showing that planets actually move in these shapes.
What are ellipses?
This unusual economic unit measures the fairness of minimum wage relative to cost of living—by comparing time worked to the local price of a well-known burger
What are minutes per Big Mac?
Crowbars make it easier to lift heavy objects with a given amount of force by applying this
What is torque?
For a simple harmonic oscillator, this quantity is zero when the mass passes through equilibrium.
What is acceleration?
When a star dies, this process ends, and can no longer support the star against its immense force of gravity
What is fusion?
Kepler’s second law states that orbiting bodies sweep out equal areas in equal times. When a planet is orbiting closer to its star, its velocity will be _____.
What is higher in magnitude/faster?
Everybody knows the metric units of kilograms and Newtons for mass and force respectively, but not as many can name the kilogram's slimy Imperial System equivalent.
What are slugs?
What is thermal conductivity?
The distance from a point charge at which the electric potential is equal to zero
What is infinity?
In cosmology, distance is measured by this dimensionless quantity
What is redshift?
Ancient Chinese astronomers recorded “guest stars” that appeared suddenly and then faded, which modern astronomers recognize as this type of stellar event.
What are supernovae?
The very real meaning of this radiation unit acronym (used mostly for scientific communication), "BED".
What is banana-equivalent-dose?
Your weight feels different when an elevator starts or stops, but not when it's moving, because a moving elevator is classified as this.
What is an inertial reference frame?
The first fundamental particle known to have an intrinsic angular momentum, or spin, of zero
What is the Higgs boson?
The cosmic microwave background, or CMB, is a curtain preventing us from observing anything from before 380,000 years after the Big Bang. This is the reason for that time constraint.
What is "the universe was opaque before then"?
(or similar, does not have to be in the form of a question)
By carefully tracking the motion of Mars, ancient astronomers observed that it sometimes moved backward in the sky before continuing forward, an effect now understood as this.
What is retrograde motion?
In 1958, an MIT fraternity measured the length of the Harvard Bridge using the height of one of their pledges. Their result? 364.4 of this unit, plus or minus 1 ear.
What are Smoots?
The phenomena responsible for the recent breakdown of Moore's Law—a law stating that the number of transistors on a microchip doubles every two years—suggesting a limit to how small traditional computers can be built
What is quantum tunneling?
For an external observer watching someone fall towards the event horizon of a black hole, this value will approach zero as time approaches infinity
What is velocity?
What is positive curvature?
Mayan astronomers built observatories like El Caracol at Chichén Itzá, aligning them with key points in the motion of this star—the brightest in the night sky—to mark the start of the rainy season.
What is Sirius?
This unit of time—equal to around 3.156 seconds— was coined by IBM in 1969 from the design objective "never to let the user wait more than a few ____ for a response", combining comically large and comically small scales
What is the nanocentury?
Geostationary orbiting satellites have to adjust their clocks to run ____ compared to clocks on Earth, thanks to the net effects of general and special relativity
What is more slowly?
(answer doesn't have to be in the form of a question)