chapter2-motion

• Scalar quantity have magnitude only, no direction.
• Vector quantities are represented by arrows
• The length of the arrow represents the magnitude of the vector
• vectors can be added using the parallelogram rule
• Vector subtraction is not commutative, so the order of the vectors does not matter.
• Length is scalar quantity.
• Acceleration is vector quantity.
• Velocity is vector quantity.
• Speed is scalar quantity.
• Displacement is vector quantity.
• Force is vector quantity.
• Distance is scalar quantity.
• Mass is scalar quantity.
• sine = opposite/hypotenuse, cosine = adjacent/hypotenuse, tangent = adjacent/opposite
• Displacement: has both magnitude and direction, vector quantity, always directed from the starting point to the end point
• Distance: has only magnitude, a scalar quantity , the length of path a long which the body moves
• Acceleration: has both magnitude and direction, a vector quantity, the rate at which velocity changes with respect to time
• Velocity: has both magnitude and direction, a vector quantity, the rate at which an object changes its displacement with respect to time
• Speed: has only magnitude, a scalar quantity, the rate at which an object changes its position with respect to time
• If a car is traveling at a constant speed of 60 kilometers per hour, what can we say about its velocity?

  Its velocity is constant
• Which units is used to measure speed and velocity?

  meters per second
• Which statements is true regarding acceleration?

  Acceleration is a vector quantity that measures the rate of change of velocity.
• A runner completes a 5-kilometer race in 25 minutes. What is the runner's average speed?

  12 km/h
• If an object moves in a circle and returns to its initial position, what is its displacement?

  Zero
• Displacement is always measured as a straight line between two points, even if the path taken was not a straight line.
• displacement: the straight-line distance and direction from the initial position of an object to its final position
• velocity: the time rate of change of displacement; it has both magnitude (speed) and direction
• acceleration: the time rate of change of velocity; it has both magnitude (change in speed or change in direction) and direction
• Average speed is the ratio of total distance to time taken.
• Average speed is the ratio of total displacement to time taken.
•  Acceleration, rate at which velocity changes with time, in terms of both speed and direction.
• Average acceleration is ratio of the change in velocity to time taken.
• In a linear motion, magnitude of displacement is equal to distance travelled.
• In a linear motion, magnitude of velocity is equal to speed.
• In uniform motion, the velocity of an object is constant and the acceleration is zero.
• In which motion, the velocity of an object is constant and the acceleration is zero?

  Uniform motion
• In uniform motion, the average velocity is equal to instantaneous velocity due to the constant velocity.
• Velocity changes if the speed changes or the direction changes or both.
• Accelerated motion occurs when there is a change in velocity over time.
• Acceleration is defined as the rate at which the velocity changes with time.