Unit 2 Review

Match the following terms with a good description of them

• Theory

• An explanation of why observed patterns happen

• Hypothesis

• A description of what effect will happen because of a given cause

• Law

• A prediction based on past evidence and experimentation

• Fact

• An observable and measurable truth.

Answer explanation

This question links to success criteria: I can differentiate between a hypothesis, theory and law and understand the importance of each.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Match the following ideas with why they are important to science

• Fact

• By observing this we gain the information we need to ask good questions and test our ideas.

• Hypothesis

• By forming this we gain a starting point to conduct an experiment and learn more.

• Law

• By learning this we can connect observed cause and effect relationships to bigger ideas and predict outcomes from similar events.

• Theory

• By using this we can reliably predict the outcome to specific events.

Answer explanation

This question links to success criteria: I can differentiate between a hypothesis, theory and law and understand the importance of each.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Watch as Blake begins to run. What happens to the sheets of paper under his feet? Why?

Mira como Blake comienza a correr. ¿Qué pasa con las hojas de papel bajo sus pies? ¿Por qué?

• Blake runs so fast that the paper appears to move backwards but actually stays still

• When Blake moves forward, the air moved into the space he had been and pushes the paper around.

• When Blake pushes backwards on the paper the paper pushes forward on him. The paper moves backward and Blake moves forward.

• Newton was wrong.

Answer explanation

This question links to success criteria: I can use Newton’s 3rd Law to explain how common motion examples work.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

When you jump up, you push the earth downwards. Why does this cause you to move upwards?

• You don't move upwards, you stay where you are and push the earth down. The earth isn't standing on anything so it easily moves.

• The question is wrong because you can't push the earth downwards. To jump you pull yourself upwards.

• Don't overthink it. it just works.

• When you push down on the earth it pushes back up on you. The upward force of the earth in reaction to your downward push makes you move up.

Answer explanation

This question links to success criteria: I can use Newton’s 3rd Law to explain how common motion examples work.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

A player throws a ball. Which of the following correctly describes the applied and reaction forces?

• The player pushing on the ball is the applied force. The ball pushing on the player is the reaction force.

• The ball pushing on the player is the applied force. The player pushing back on the ball is the reaction force.

• The player's hand moving is the applied force. The ball moving is the reaction force.

• The player pushing on the ball is the applied force. The wind pushing on the ball is the reaction force.

Answer explanation

This question links to success criteria: I can identify action and reaction forces.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

When you drop a rubber ball on the floor it bounces back. During the bounce, which of the following describes the applied and reaction forces correctly?

• The ground pulled the ball down (applied force) but the air pushes it back up (reaction force)

• Gravity pulled the ball down (applied force) and when it hits the ground the ground pushes it back up (reaction force)

• The air pushes the ball upward (applied force) while the person pushes it down (reaction force).

• Darth Vader pulls it down (applied force) but Obi-wan pushes it up (reaction force).

Answer explanation

This question links to success criteria: I can identify action and reaction forces.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Is there an outside force acting to create the motion you see in the animation?

• The object's speed does not change, so there is no force

• The direction the object moves is changing, there must be an outside force.

• The center of the object doesn't move, so there is no outside force.

• The object is above the ground, there is a downward force.

Answer explanation

This question links to success criteria: I can determine whether an outside net force is acting upon an object based on its motion.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Which statement best summarizes the scientific concept shown in the cartoon?

• A falling body accelerates at a constant speed.

• The motion of an object is constantly changing due to magnetic forces.

• The force of friction causes an object in motion to move faster.

• A body in motion will remain in motion unless influenced by an outside force.

Answer explanation

This question links to success criteria: I can determine whether an outside net force is acting upon an object based on its motion.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

What best describes the balance of forces (net force) acting on the barbell while the weightlifter holds it steady (at rest) above his head?

• The object is not in motion, so there the forces are balanced.

• It is heavy, so the downward force must be stronger.

• It is heavy but he is strong, so the upward force must be stronger

• It you push and pull at the same time it will move to the side.

Answer explanation

This question links to success criteria: I can determine whether an outside net force is acting upon an object based on its motion.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Why is it important that scientists modify scientific theories when important new information is discovered?

• to confuse other scientists

• to keep the theory interesting and fresh

• to keep the theory as accurate and effective as possible

• to make sure the general public does not understand the theory

Answer explanation

This question links to success criteria: I can differentiate between a hypothesis, theory and law and understand the importance of each.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.