Gravity is a fundamental force of nature that causes objects to attract each other. It is responsible for the formation and motion of celestial bodies such as stars, planets, and moons.

**Law of Universal Gravitation:**Proposed by Sir Isaac Newton, this law states that every particle of matter in the universe attracts every other particle with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.**Acceleration due to Gravity:**Near the surface of the Earth, the acceleration due to gravity is approximately 9.81 m/s^{2}. This value varies slightly with location and altitude.**Gravitational Field:**The region around an object where a force due to gravity is experienced by other objects.**Weight:**The force with which an object is attracted towards the center of the Earth or any other celestial body.

The force of gravity between two objects can be calculated using the following equation:

F = G * (m1 * m2) / r^{2}

where F is the force of gravity, G is the gravitational constant (approximately 6.674 × 10^{-11} Nm^{2}/kg^{2}), m1 and m2 are the masses of the two objects, and r is the distance between their centers.

- Understand the concept of gravitational force and how it varies with mass and distance.
- Practice solving problems involving the law of universal gravitation and the calculation of gravitational force.
- Learn to differentiate between weight and mass, and how they are related in the presence of gravity.
- Explore the historical and scientific significance of the concept of gravity, including its role in the formation of the universe and the laws of planetary motion.

Worksheet/Answer key

Electromagnetism Worksheet/Answer key

Electromagnetism Worksheet/Answer key

Electromagnetism

PHYSICAL SCIENCE (NGSS)

Energy

Students who demonstrate understanding can:

Design, build, and refine a device that works within given constraints to convert one form of energy into another form of energy.