6th Grade Science Fall Final Review

What is a key characteristic of a liquid?

• It has a definite shape and volume

• It has a definite volume but no definite shape

• It has no volume or shape

• It has a definite shape but no volume

Answer explanation

A key characteristic of a liquid is that it has a definite volume but no definite shape, allowing it to take the shape of its container while maintaining a consistent volume.

Tags

NGSS.MS-PS1-4

Which statement best describes molecules in a gas?

• They are tightly packed together

• They move slowly and orderly

• They move rapidly and freely

• They have a fixed arrangement

Answer explanation

In a gas, molecules are not tightly packed; they move rapidly and freely in all directions, unlike solids or liquids where molecules are more ordered and closely arranged.

What type of mixture is salad dressing made with oil and vinegar?

• Compound

• Element

• Homogeneous mixture

• Heterogeneous mixture

Answer explanation

Salad dressing made with oil and vinegar is a heterogeneous mixture because the oil and vinegar do not fully combine, allowing you to see distinct layers or phases. This contrasts with homogeneous mixtures, where components are uniformly distributed.

Which property is characteristic of metals?

• They are brittle when hammered

• They conduct electricity well

• They are dull in appearance

• They are poor heat conductors

Answer explanation

Metals are known for their ability to conduct electricity well due to the presence of free-moving electrons. This property distinguishes them from non-metals, which are typically poor conductors.

Tags

NGSS.MS-PS3-3

What happens when a soccer ball rolling across grass eventually stops?

• Friction causes it to stop

• Gravity pulls it down

• Air pressure stops it

• Mass causes the stop

Answer explanation

Friction between the soccer ball and the grass slows it down and eventually brings it to a stop. This is the primary force acting against the ball's motion, making 'Friction causes it to stop' the correct answer.

Tags

NGSS.MS-PS2-2

In a balloon rocket, what causes the forward motion?

• Gravitational force

• Air pressure inside

• Backward force of released air

• Upward air pressure

Answer explanation

The forward motion of a balloon rocket is caused by the backward force of released air. As air escapes from the balloon, it pushes the balloon in the opposite direction, demonstrating Newton's third law of motion.

What force must be overcome to slide a heavy box across the floor?

• Air resistance

• Friction

• Mass

• Gravity

Answer explanation

To slide a heavy box across the floor, the primary force that must be overcome is friction. Friction is the resistance that occurs between the box and the floor, making it necessary to apply a force to move the box.

When is a force considered balanced?

• When an object speeds up

• When motion continues unchanged

• When an object slows down

• When direction changes

Answer explanation

A force is considered balanced when the net force acting on an object is zero, resulting in no change in motion. Therefore, the correct choice is 'When motion continues unchanged', indicating that the object remains at rest or moves at a constant speed.

Tags

NGSS.HS-PS2-1

What type of energy does a compressed spring have?

• Kinetic energy

• Potential energy

• Thermal energy

• Chemical energy

Answer explanation

A compressed spring stores energy due to its position. This stored energy is called potential energy, as it has the potential to do work when released.

Tags

NGSS.MS-PS3-2

Where does a roller coaster have the most kinetic energy?

• At the highest point

• At the lowest point

• At the middle point

• At the starting point

Answer explanation

A roller coaster has the most kinetic energy at the lowest point because potential energy is converted to kinetic energy as it descends. At the highest point, the energy is mostly potential, while at the lowest point, it is maximized as kinetic.

Tags

NGSS.MS-PS3-1

NGSS.MS-PS3-5