Gravity

What happens to gravity as distance increases?

• It gets stronger

• It stays the same

• It gets weaker

• It disappears

Answer explanation

As distance from a mass increases, the gravitational force decreases. This is described by the inverse square law, which states that gravity weakens with increasing distance, making 'It gets weaker' the correct choice.

What is mass?

• The pull of gravity on an object

• The amount of matter in an object

• The distance between objects

• The measure of weight

Answer explanation

Mass is defined as the amount of matter in an object, making it the correct choice. It is distinct from weight, which is the force of gravity acting on that mass.

Which planet has the strongest gravity?

• Mars

• Jupiter

• Earth

• Venus

Answer explanation

Jupiter has the strongest gravity of all planets in our solar system due to its massive size and composition. Its gravity is about 24.79 m/s², significantly stronger than Mars, Earth, or Venus.

Tags

NGSS.MS-PS2-4

What is the unit for weight?

• Grams

• Kilograms

• Newtons

• Pounds

Answer explanation

Weight is a measure of force and is expressed in Newtons in the International System of Units (SI). While grams, kilograms, and pounds measure mass, Newtons specifically quantify weight as a force due to gravity.

Tags

NGSS.HS-PS2-4

Who developed the theory of gravity?

• Albert Einstein

• Galileo Galilei

• Isaac Newton

• Nikola Tesla

Answer explanation

Isaac Newton developed the theory of gravity in the 17th century, formulating the law of universal gravitation, which describes the gravitational attraction between masses. Einstein and Galileo contributed to physics but not specifically to gravity theory.

Tags

NGSS.HS-PS2-4

Fill in the blank: The process of water movement through a plant and its evaporation is called ________.

• Photosynthesis

• Transpiration

• Germination

• Condensation

Answer explanation

The correct answer is 'Transpiration' because it refers to the process of water movement through a plant and its evaporation from aerial parts, primarily leaves. Photosynthesis is about energy production, while germination and condensation are unrelated.

A force of attractions between two objects.

• Air Resistance

• Gravity

• Acceleration

• Velocity

Answer explanation

Gravity is the force of attraction between two objects with mass, making it the correct answer. Air resistance opposes motion, while acceleration and velocity describe motion, not attraction.

Tags

NGSS.MS-PS2-4

Which of these objects exerts a gravitational pull? (Click all that apply.)

• The Sun

• The Earth

• The Moon

• your pencil

• a fly

Answer explanation

All objects with mass exert a gravitational pull, including the Sun, Earth, Moon, your pencil, and a fly. Therefore, all the listed objects exert a gravitational pull.

Tags

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NGSS.MS-ESS1-1

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Force is measured in?

• Newtons

• Newts

• Watts

Answer explanation

Force is measured in Newtons, named after Sir Isaac Newton. Newts are amphibians, and Watts measure power, not force. Therefore, the correct answer is Newtons.

Students described the amount of force needed to change the motion for each ball from idle to rolling.  Which statement is true?*

• The beach ball has less mass, but it took more force to make it roll.

• The bowling ball has less mass, but it took more force to make it roll.

• The beach ball has more mass, therefore it took less force to make it roll.

• The bowling ball has more mass, therefore, it took more force to make it roll.

Answer explanation

The bowling ball has more mass than the beach ball, which means it requires more force to change its state from idle to rolling, according to Newton's second law of motion (F=ma). Thus, the correct statement is that the bowling ball took more force.

Tags

NGSS.MS-PS2-2