CAST Science 8 Practice Test 1

Front

What is kinetic energy?

Back

Kinetic energy is the energy an object possesses due to its motion. It is calculated using the formula KE = 1/2 mv², where m is mass and v is velocity.

Front

How does the mass of an object affect its kinetic energy?

Back

The kinetic energy of an object increases with its mass. If the mass increases while the velocity remains constant, the kinetic energy will also increase.

Front

What is the relationship between kinetic energy and the depth of impact craters?

Back

The kinetic energy of an object just before impact is proportional to the depth of the crater it forms; greater kinetic energy results in a deeper crater.

Front

What happens to the sea urchin population when the kelp population increases?

Back

As the kelp population increases, the sea urchin population decreases due to increased competition for food and resources.

Front

What is a balanced chemical reaction?

Back

A balanced chemical reaction has the same number of atoms of each element on both sides of the equation, ensuring that mass is conserved.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction; the total mass of reactants equals the total mass of products.

Front

What is the significance of measuring mass before and after a chemical reaction?

Back

Measuring mass before and after a chemical reaction helps to confirm the law of conservation of mass, showing that the total mass remains constant.

Front

What is a food web?

Back

A food web is a complex network of feeding relationships among organisms in an ecosystem, showing how energy and nutrients flow through the environment.

Front

How do changes in one population affect others in a food web?

Back

Changes in one population, such as an increase or decrease, can have cascading effects on other populations in the food web, impacting their survival and reproduction.

Front

What is the role of producers in an ecosystem?

Back

Producers, such as plants and algae, convert sunlight into energy through photosynthesis, forming the base of the food web.