Speed/Velocity
What is the main difference between speed and velocity?
Speed is a scalar quantity, meaning it only has magnitude. Velocity is a vector quantity, meaning it has both magnitude and direction.
What is distance?
Distance is the total length of the path traveled by an object, regardless of direction.
What is acceleration?
Acceleration is the rate at which an object’s velocity changes over time.
What is Newton's First Law of Motion?
An object at rest stays at rest, and an object in motion stays in motion at a constant velocity unless acted upon by an unbalanced force.
What happens to an object when balanced forces act on it?
The object remains at rest or continues to move at a constant velocity.
If a car travels 60 kilometers in 1 hour, what is its speed?
The speed is 60 km/h.
What is displacement?
Displacement is the shortest straight-line distance between the starting point and the ending point, including direction.
If a car’s velocity increases from 0 to 20 m/s in 5 seconds, what is its acceleration?
The acceleration is 4 m/s² (calculated by 20m/s − 0m/s / 5s)
Which of Newton's laws is also known as the law of inertia?
Newton's First Law of Motion.
What are unbalanced forces?
Unbalanced forces occur when the net force acting on an object is not zero, causing the object to accelerate.
A runner completes a 400-meter track in 100 seconds, but ends up back where they started. What is the runner’s velocity?
The velocity is 0 m/s because the displacement is zero.
A person walks 3 km east and then 4 km north. What is the total distance they walked?
The total distance walked is 7 km.
What is the unit of acceleration in the SI system?
The unit of acceleration is meters per second squared (m/s²).
What is the formula associated with Newton's Second Law of Motion?
The formula is F=ma (Force equals mass times acceleration).
If a book is lying on a table and not moving, what can you say about the forces acting on it?
The forces are balanced; the force of gravity is balanced by the normal force from the table.
A cyclist travels 15 km north in 1 hour, then 10 km south in 30 minutes. What is the cyclist’s average velocity?
The displacement is 5 km north, and the total time is 1.5 hours, so the average velocity is approximately 3.33 km/h north.
A person walks 3 km east and then 4 km north. What is the total displacement?
The displacement is 5 km northeast (using the Pythagorean theorem, (32+42) Square root = 5
A cyclist slows down from 15 m/s to 5 m/s in 2 seconds. What is the cyclist’s acceleration?
The acceleration is -5 m/s² (negative because it’s deceleration).
According to Newton's Third Law, what happens when you push against a wall?
The wall pushes back with an equal and opposite force.
A car accelerates forward when you press the gas pedal. What does this tell you about the forces acting on the car?
The forces are unbalanced, with a greater force pushing the car forward than resisting it.
If a car moves east at 50 km/h for 2 hours and then west at 40 km/h for 1 hour, what is the car's average speed and average velocity?
Average speed is 46.67 km/h, and the average velocity is 20 km/h east.
A person walks 4 km east and then 3 km west. What is the person’s displacement?
The displacement is 1 km east.
If a car accelerates at 3 m/s² for 10 seconds, how much does its velocity increase?
The velocity increases by 30 m/s (calculated by 3m/s2×10s)
A 10 kg object accelerates at 2 m/s². What is the force acting on the object according to Newton's Second Law?
The force is 20 N (calculated by F=10kg × 2m/s2)
If two teams are playing tug-of-war and neither team is moving, what can you say about the forces in the rope?
The forces are balanced because both teams are pulling with equal force in opposite directions.