Question

1. summarize galileos contributions to science. 12. compare and contrast mass and weight. 13. what is gravity and what does the strength of gravity depend upon?

Explanation:

1. Galileo made several key contributions. He improved the telescope and made astronomical discoveries like the moons of Jupiter. He also conducted experiments on falling - bodies, challenging Aristotelian views and laying groundwork for modern physics.
2. Mass is a measure of the amount of matter in an object, a scalar quantity that is constant everywhere. Weight is the force exerted on an object due to gravity, a vector quantity that varies depending on the gravitational field strength. Mathematically, $W = mg$, where $W$ is weight, $m$ is mass, and $g$ is the acceleration due to gravity.
3. Gravity is a fundamental force of attraction between two masses. The strength of gravity between two objects depends on the masses of the objects and the distance between their centers. According to Newton's law of universal gravitation, $F = G\frac{m_1m_2}{r^2}$, where $F$ is the gravitational force, $G$ is the gravitational constant, $m_1$ and $m_2$ are the masses of the two objects, and $r$ is the distance between their centers.

Answer:

1. Improved telescope, made astronomical discoveries, conducted falling - body experiments.
2. Mass is amount of matter, constant; weight is gravitational force, varies with $g$ ($W = mg$).
3. Gravity is force of attraction between masses. Its strength depends on object masses and distance between them ($F = G\frac{m_1m_2}{r^2}$).