Please describe a constant in an experiment.
3 answers
something that does not change. For example it might be the ratio of weight to mass on earth.
Could that really be an experiment?
Sure
F = m a
on a flat horizontal greasy table pull an object with a spring and measure the force and acceleration
then mass * a = measured force
or mass = measured force/measured a
now hang the mass from the same spring and measure the force
we know the mass from our earlier experiment
so
measured Force = weight = mass * something
that something will be the same for various sized and densities of objects as I repeat the experiment
we call it the constant g which on earth is about 9.81 m/s^2
On Moon that constant will be about one sixth of its value on earth
BUT
Newton says they are related by a more general constant, the Gravitational constant G
where
F = G M1 M2 / distance between^2
F = m a
on a flat horizontal greasy table pull an object with a spring and measure the force and acceleration
then mass * a = measured force
or mass = measured force/measured a
now hang the mass from the same spring and measure the force
we know the mass from our earlier experiment
so
measured Force = weight = mass * something
that something will be the same for various sized and densities of objects as I repeat the experiment
we call it the constant g which on earth is about 9.81 m/s^2
On Moon that constant will be about one sixth of its value on earth
BUT
Newton says they are related by a more general constant, the Gravitational constant G
where
F = G M1 M2 / distance between^2
1 answer