Question

fill in the blanks.
the scientist who determined that there is a gravitational force between any objects that have mass was .
the scientist who first measured this force was
get it? summarize how the gravitational force can be used to explain the phenomenon of a planet orbiting the sun.
science notebook · gravitation
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Explanation:

1. The first blank: Newton determined that there is a gravitational force between any objects that have mass.
2. The second blank: Henry Cavendish was the scientist who first measured the gravitational constant (related to gravitational force).
3. For the explanation part: The gravitational force \( F = G\frac{m_1m_2}{r^2} \) (Newton's law of universal gravitation) acts as the centripetal force for a planet orbiting the Sun. The centripetal force \( F_c=\frac{mv^2}{r} \) (or \( F_c = m\omega^2r \)) keeps the planet in its orbital path. Equating the gravitational force to the centripetal force (\( G\frac{Mm}{r^2}=\frac{mv^2}{r} \), where \( M \) is the Sun's mass, \( m \) is the planet's mass, \( r \) is the orbital radius, and \( v \) is the orbital velocity) allows us to derive orbital properties like velocity, period, etc. This shows how gravitational force provides the necessary centripetal force for planetary orbits, explaining why planets follow elliptical (or nearly circular) paths around the Sun.

Answer:

1. The scientist who determined that there is a gravitational force between any objects that have mass was Isaac Newton.
2. The scientist who first measured this force (gravitational constant) was Henry Cavendish.
3. Explanation: The gravitational force (from Newton's law \( F = G\frac{m_1m_2}{r^2} \)) acts as the centripetal force (\( F_c=\frac{mv^2}{r} \)) for a planet orbiting the Sun. Equating these (\( G\frac{Mm}{r^2}=\frac{mv^2}{r} \)) explains the planet’s orbital motion, as the gravitational attraction provides the necessary inward force to keep the planet in its orbit around the Sun.