IsaacUnit4StudyGuide

Question 1

What is Newton’s First Law of Motion?

Answer 1

An object will remain at rest or move in a straight line at constant speed unless acted upon by an external force.

Question 2

Give an example of Newton’s First Law.

Answer 2

A ball on a flat surface won’t move unless pushed.

Question 3

What is Newton’s Second Law of Motion?

Answer 3

The acceleration of an object depends on the net force acting on it and its mass, expressed as F=ma.

Question 4

Give an example of Newton’s Second Law.

Answer 4

A heavier cart requires more force to accelerate than a lighter one.

Question 5

What is Newton’s Third Law of Motion?

Answer 5

For every action, there is an equal and opposite reaction.

Question 6

Give an example of Newton’s Third Law.

Answer 6

When you push against a wall, the wall pushes back with the same force.

Question 7

What is force?

Answer 7

A push or pull exerted on an object.

Question 8

What is magnitude?

Answer 8

The size or amount of a quantity.

Question 9

What is a scalar quantity?

Answer 9

A quantity that has only magnitude, such as speed or mass.

Question 10

What is a vector quantity?

Answer 10

A quantity that has both magnitude and direction, such as velocity or force.

Question 11

What is mechanical equilibrium?

Answer 11

When an object is not experiencing a change in motion (forces are balanced).

Question 12

What is gravity?

Answer 12

The force that pulls objects toward the center of the Earth.

Question 13

What is net force?

Answer 13

The vector sum of all forces acting on an object.

Question 14

What are balanced forces?

Answer 14

Forces that are equal in magnitude and opposite in direction, resulting in no change in motion.

Question 15

What are unbalanced forces?

Answer 15

Forces that are not equal in magnitude or direction, causing acceleration or a change in motion.

Question 16

What is drag?

Answer 16

A resistive force that acts opposite to the motion of an object moving through a fluid (like air or water).

Question 17

What is speed?

Answer 17

The magnitude of the rate of change of an object’s movement (a scalar quantity).

Question 18

What is velocity?

Answer 18

The rate of change of an object’s movement with both magnitude and direction (a vector quantity).

Question 19

What is acceleration?

Answer 19

The rate of change of velocity over time.

Question 20

What is displacement?

Answer 20

The change in position of an object, measured as a vector.

Question 21

What is momentum?

Answer 21

The product of an object’s mass and velocity, describing how difficult it is to stop a moving object.

Question 22

What is the conservation of momentum?

Answer 22

The principle that momentum is neither created nor destroyed in a closed system.

Question 23

What is potential energy?

Answer 23

Stored energy due to an object’s position or condition.

Question 24

What is elastic potential energy?

Answer 24

Energy stored in stretched or compressed objects, like a rubber band or a spring.

Question 25

What is kinetic energy?

Answer 25

The energy an object has due to its motion, depending on mass and speed.

Question 26

What is friction?

Answer 26

The force that resists motion when two surfaces are in contact.

Question 27

What is an action force?

Answer 27

The force exerted by one object on another.

Question 28

What is a reaction force?

Answer 28

The equal and opposite force exerted by the second object back on the first.

Question 29

What is terminal velocity?

Answer 29

The constant speed a falling object reaches when air resistance equals gravitational force.

Question 30

How did the Apollo 15 Hammer-Feather Drop experiment demonstrate gravity?

Answer 30

It showed that in the absence of air resistance, all objects fall at the same rate regardless of mass.

Question 31

What is the difference between distance and displacement?

Answer 31

Distance is the total path traveled (scalar), while displacement is the shortest straight-line change in position (vector).

Question 32

How does air resistance affect a skydiver’s fall?

Answer 32

It opposes gravity, slowing acceleration and allowing a safe landing with a parachute.

Question 33

What is the relationship between force, mass, and acceleration?

Answer 33

Force equals mass times acceleration (F=ma).

Question 34

What did Galileo’s experiment prove about falling objects?

Answer 34

Objects of different masses fall at the same rate in the absence of air resistance.

Question 35

What is the role of lift in an airplane?

Answer 35

Lift is the upward force that opposes gravity and allows a plane to stay in the air.

Question 36

How does drag affect an airplane?

Answer 36

Drag opposes the forward motion of an airplane, slowing it down.

Question 37

How does Newton’s Third Law apply to a balloon-powered car?

Answer 37

The air rushing out (action force) pushes the car forward (reaction force).

Question 38

Why do astronauts float in space?

Answer 38

They are in free fall, continuously falling toward Earth but never hitting it due to orbital motion.

Question 39

True or False: A heavier object falls faster than a lighter object in a vacuum.

Answer 39

False. In a vacuum, all objects fall at the same rate regardless of mass.

Question 40

Multiple Choice: What happens when unbalanced forces act on an object? A) The object remains at rest B) The object accelerates C) The object moves in circles D) The object disappears

Answer 40

B) The object accelerates.

Question 41

What is the scientific method, and why is it important in physics?

Answer 41

The scientific method is a structured approach to investigating questions, forming hypotheses, and testing theories through experiments to ensure repeatability and reliability.

Question 42

What are the key components of a lab report, and why is each important?

Answer 42

A lab report includes a hypothesis (prediction), materials (tools used), procedure (steps taken), results (data collected), and conclusion (what was learned). Each part ensures the experiment is clear and repeatable.

Question 43

Why do scientists repeat experiments multiple times before accepting a theory?

Answer 43

To ensure accuracy, identify errors, and confirm that results are reliable and not just a one-time occurrence.

Question 44

Multiple Choice: Which of the following best describes Newton's Second Law? A) An object at rest stays at rest B) Acceleration depends on force and mass C) Every action has an equal and opposite reaction D) The net force is always zero

Answer 44

B) Acceleration depends on force and mass.

Question 45

True or False: A skydiver will accelerate indefinitely as they fall.

Answer 45

False. Once air resistance equals the force of gravity, the skydiver reaches terminal velocity.

Question 46

How did Galileo disprove Aristotle’s idea that heavier objects fall faster?

Answer 46

He conducted experiments by dropping objects of different masses and showed they fell at the same rate in the absence of air resistance.

Question 47

Why do scientists sometimes reject old theories?

Answer 47

New evidence or better experiments can show flaws in old theories, leading to improved or revised scientific understanding.

Question 48

Multiple Choice: Why does a car stop when you take your foot off the gas? A) Because of inertia B) Because of friction and air resistance C) Because of Newton’s Third Law D) Because the engine stops working

Answer 48

B) Because of friction and air resistance.

Question 49

Explain how Newton’s Third Law applies to walking.

Answer 49

When you push back on the ground with your foot (action), the ground pushes forward on you (reaction), allowing you to move forward.

Question 50

True or False: Scientists can prove theories 100% correct.

Answer 50

False. Theories are always open to new evidence and revision.

Question 51

What is the difference between a hypothesis and a theory?

Answer 51

A hypothesis is a testable prediction, while a theory is a well-supported explanation based on repeated experiments and evidence.

Question 52

Multiple Choice: What is the primary force acting on a skydiver just after jumping from a plane? A) Air resistance B) Gravity C) Momentum D) Drag

Answer 52

B) Gravity.

Question 53

Explain why air resistance increases as a skydiver speeds up.

Answer 53

As velocity increases, the skydiver collides with more air molecules per second, increasing the opposing force of air resistance.

Question 54

Why does an airplane need lift to stay in the air?

Answer 54

Lift counteracts gravity and allows the airplane to remain airborne.

Question 55

What role does friction play in stopping a moving object?

Answer 55

Friction opposes motion and slows down or stops an object by converting kinetic energy into heat.

Question 56

Multiple Choice: What happens if the net force on an object is zero? A) The object moves in a straight line B) The object remains at rest or moves at constant velocity C) The object accelerates D) The object speeds up

Answer 56

B) The object remains at rest or moves at constant velocity.

Question 57

Why do astronauts feel weightless in orbit?

Answer 57

They are in free fall, continuously falling toward Earth but moving forward fast enough to stay in orbit.

Question 58

Why was Newton’s discovery of gravity important for science?

Answer 58

It provided a universal explanation for motion on Earth and in space, forming the basis for classical mechanics.

Question 59

True or False: If no forces act on an object, it will eventually stop moving.

Answer 59

False. According to Newton’s First Law, an object in motion stays in motion unless acted upon by an external force.

Question 60

Why do engineers study aerodynamics when designing airplanes and cars?

Answer 60

To reduce drag and increase efficiency by minimizing air resistance.

Question 61

How can we test the effect of mass on acceleration in a lab setting?

Answer 61

By using ramps and different weighted objects while measuring acceleration with a motion sensor or timer.

Question 62

How does the conservation of momentum apply to a rocket launch?

Answer 62

The momentum of expelled gases pushes back, propelling the rocket forward in space.