What is Velocity(āĻŦā§āĻ) & Acceleration(āϤā§āĻŦā§°āĻŖ)
Velocity tells us how fast an object moves and in which direction. (āĻŦā§āĻā§ āĻāĻŽāĻžāĻ āĻāϝāĻŧ āϝ⧠āĻā§āύ⧠āĻŦāϏā§āϤ⧠āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āĻā§°ā§ āĻā§āύ āĻĻāĻŋāĻļāϤ āĻāϤāĻŋ āĻā§°āĻŋ āĻāĻā§āĨ¤)
- It is a vector quantity. (āĻ āĻāĻāĻž āĻā§āĻā§āĻā§° ā§°āĻžāĻļāĻŋ (Vector Quantity)āĨ¤)
- It has both magnitude and direction.{āĻāϝāĻŧāĻžāϤ āĻŽāĻžāύ (Magnitude) āĻā§°ā§ āĻĻāĻŋāĻļ (Direction)} āĻĻā§āϝāĻŧā§āĻāĻžāĻ āĻĨāĻžāĻā§āĨ¤
Formula / āϏā§āϤā§ā§° = Velocity = Displacement / Timeâ
Unit / āĻāĻāĻ: m/s, km/h
Example / āĻāĻĻāĻžāĻšā§°āĻŖ: A car moves at 20 m/s east. (āĻāĻāύ āĻāĻžāĻĄāĻŧā§ āĻĒā§āĻŦ āĻĻāĻŋāĻļāϞ⧠20 m/s āĻŦā§āĻā§ āĻāϤāĻŋ āĻā§°āĻŋāĻā§āĨ¤)
Velocity = 20 m/s east (āĻŦā§āĻ = 20 m/s āĻĒā§āĻŦ āĻĻāĻŋāĻļā§)
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What is Acceleration ? / āϤā§āĻŦā§°āĻŖ āĻāĻŋ ?
Acceleration tells us how quickly velocity changes. (āϤā§āĻŦā§°āĻŖā§ āĻŦā§āĻ āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āϏāϞāύāĻŋ āĻšāϝāĻŧ āϤāĻžāĻ āĻŦā§āĻāĻžāϝāĻŧāĨ¤)
- It can mean speeding up, slowing down, or changing direction.
- It is a vector quantity.
Formula / āϏā§āϤā§ā§° : Acceleration = Change in Velocity ÷ Time â
Unit / āĻāĻāĻ: m/s²
āϤā§āĻŦā§°āĻŖ āĻāĻŋ ?
- āϤā§āĻŦā§°āĻŖā§ āĻāĻŽāĻžāĻ āĻāϝāĻŧ āϝ⧠āĻŦā§āĻ āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āϏāϞāύāĻŋ āĻšāϝāĻŧāĨ¤
- āĻ āĻāϤāĻŋ āĻŦā§āĻĻā§āϧāĻŋ, āĻāϤāĻŋ āĻšā§ā§°āĻžāϏ āĻŦāĻž āĻĻāĻŋāĻļ āϏāϞāύāĻŋ āĻŦā§āĻāĻžāĻŦ āĻĒāĻžā§°ā§āĨ¤
- āĻ āĻāĻāĻž āĻā§āĻā§āĻā§° ā§°āĻžāĻļāĻŋ (Vector Quantity)āĨ¤
āϤā§āĻŦā§°āĻŖ = āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦā§°ā§āϤāύ ÷ āϏāĻŽāϝāĻŧ
āϏāĻžāϧāĻžā§°āĻŖ āĻāĻāĻ: m/s²
Example / āĻāĻĻāĻžāĻšā§°āĻŖ: A car changes from 10 m/s east to 20 m/s east in 5 s. (āĻāĻāύ āĻāĻžāĻĄāĻŧā§ā§° āĻŦā§āĻ 10 m/s āĻĒā§āĻŦā§° āĻĒā§°āĻž 20 m/s āĻĒā§āĻŦāϞ⧠5 āĻā§āĻā§āĻŖā§āĻĄāϤ āĻŦā§āĻĻā§āϧāĻŋ āĻĒāĻžāϝāĻŧāĨ¤)
Formula / āϏā§āϤā§ā§° : Acceleration = Change in Velocity / Time
A = (20 − 10)/5 = 2 m/s2
Acceleration = 2 m/s² east (āϤā§āĻŦā§°āĻŖ = 2 m/s² āĻĒā§āĻŦ āĻĻāĻŋāĻļā§)
What's the Difference ? / āĻĒāĻžā§°ā§āĻĨāĻā§āϝ āĻāĻŋ ?
Velocity (āĻŦā§āĻ) = Speed + Direction // (āĻŦā§āĻ = āĻĻā§ā§°ā§āϤāĻŋ + āĻĻāĻŋāĻļ)
Acceleration (āϤā§āĻŦā§°āĻŖ) = Change in Velocity ÷ Time //(āϤā§āĻŦā§°āĻŖ = āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦā§°ā§āϤāύ ÷ āϏāĻŽāϝāĻŧ)
Difference between āĻŦā§āĻ (Velocity) vs āϤā§āĻŦā§°āĻŖ (Acceleration) : Click Here
- Velocity → How fast + Which direction ? (āĻŦā§āĻ → āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ + āĻā§āύ āĻĻāĻŋāĻļ ?)
- Acceleration → How quickly velocity changes ? (āϤā§āĻŦā§°āĻŖ → āĻŦā§āĻ āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āϏāϞāύāĻŋ āĻšāϝāĻŧ ?)
MCQ / āĻŦāĻšā§-āĻŦāĻŋāĻāϞā§āĻĒā§ āĻĒā§ā§°āĻļā§āύ :: Velocity vs Acceleration MCQ :: āĻŦā§āĻ āĻā§°ā§ āϤā§āĻŦā§°āĻŖ MCQ
Q. A bike moves at 50 km/h towards north. What is it ? (āĻĒā§ā§°āĻļā§āύāĻ āĻāĻāύ āĻŦāĻžāĻāĻ 50 km/h āĻŦā§āĻā§ āĻāϤā§āϤ⧰ āĻĻāĻŋāĻļāϞ⧠āĻāϤāĻŋ āĻā§°āĻŋāĻā§āĨ¤ āĻ āĻāĻŋ ?)
(a) Speed (āĻĻā§ā§°ā§āϤāĻŋ) (b) Distance (āĻĻā§ā§°āϤā§āĻŦ) (c) Velocity (āĻŦā§āĻ) (d) Acceleration (āϤā§āĻŦā§°āĻŖ)
Ans / āĻāϤā§āϤ⧰: (c) Velocity (āĻŦā§āĻ)
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Direction (north) is given, so it is velocity. āĻŦā§āϝāĻžāĻā§āϝāĻž: āĻāϝāĻŧāĻžāϤ āĻĻāĻŋāĻļ (āĻāϤā§āϤ⧰) āĻāϞā§āϞā§āĻ āĻāĻā§, āϏā§āϝāĻŧā§ āĻ āĻŦā§āĻ (Velocity)āĨ¤
1. Velocity is defined as: (ā§§. āĻŦā§āĻāĻ āĻāĻŋ āĻŦā§āϞāĻŋ āϏāĻāĻā§āĻāĻžāϝāĻŧāĻŋāϤ āĻā§°āĻž āĻšāϝāĻŧ ?)
(a) Distance ÷ Time (b) Speed + Direction (c) Force × Time (d) Mass × Velocity
Ans / āĻāϤā§āϤ⧰: (b) Speed + Direction
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Velocity includes both speed and direction. (āĻŦā§āĻāϤ āĻĻā§ā§°ā§āϤāĻŋ āĻā§°ā§ āĻĻāĻŋāĻļ āĻĻā§āϝāĻŧā§āĻāĻžāĻ āĻĨāĻžāĻā§āĨ¤)
2. Acceleration is the rate of change of: ⧍. āϤā§āĻŦā§°āĻŖ āĻāĻŋāĻšā§° āĻĒā§°āĻŋāĻŦā§°ā§āϤāύ⧰ āĻšāĻžā§° ?
(a) Distance (b) Speed (c) Velocity (d) Force
Ans / āĻāϤā§āϤ⧰: (c) Velocity
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Acceleration measures how quickly velocity changes. (āϤā§āĻŦā§°āĻŖā§ āĻŦā§āĻ āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āϏāϞāύāĻŋ āĻšāϝāĻŧ āϤāĻžāĻ āĻŦā§āĻāĻžāϝāĻŧāĨ¤)
3. The SI unit of velocity is: (ā§Š. āĻŦā§āĻā§° SI āĻāĻāĻ āĻāĻŋ ?)
(a) m/s² (b) km/h (c) m/s (d) N
Ans / āĻāϤā§āϤ⧰: (c) m/s
4. The SI unit of acceleration is: ā§Ē. āϤā§āĻŦā§°āĻŖā§° SI āĻāĻāĻ āĻāĻŋ ?
(a) m/s (b) m/s² (c) km/h (d) N
Ans / āĻāϤā§āϤ⧰: (b) m/s²
5. Which of the following is an example of velocity? ā§Ģ. āϤāϞ⧰ āĻā§āύāĻā§ āĻŦā§āĻā§° āĻāĻĻāĻžāĻšā§°āĻŖ ?
(a) 60 km/h (b) 10 m/s east (c) 5 m (d) 20 s
Ans / āĻāϤā§āϤ⧰: (b) 10 m/s east
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Direction is given, so it is velocity. (āĻĻāĻŋāĻļ āĻāϞā§āϞā§āĻ āĻāĻā§, āϏā§āϝāĻŧā§ āĻ āĻŦā§āĻāĨ¤)
6. Which quantity is a vector ? (ā§Ŧ. āϤāϞ⧰ āĻā§āύāĻā§ āĻā§āĻā§āĻā§° ā§°āĻžāĻļāĻŋ ?)
(a) Distance (b) Time (c) Velocity (d) Mass
Ans / āĻāϤā§āϤ⧰: (c) Velocity
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Velocity is a vector quantity because it has direction.
Example: 20 m/s east, Here, both speed (20 m/s) and direction (east) are given.
āĻŦā§āϝāĻžāĻā§āϝāĻž: āĻŦā§āĻ (Velocity) āĻāĻāĻž āĻā§āĻā§āĻā§° ā§°āĻžāĻļāĻŋ āĻāĻžā§°āĻŖ āĻāϝāĻŧāĻžāϤ āĻĻāĻŋāĻļ āĻĨāĻžāĻā§āĨ¤ āĻāĻĻāĻžāĻšā§°āĻŖ: 20 m/s āĻĒā§āĻŦ āĻĻāĻŋāĻļā§, āĻāϝāĻŧāĻžāϤ āĻĻā§ā§°ā§āϤāĻŋ (20 m/s) āĻā§°ā§ āĻĻāĻŋāĻļ (āĻĒā§āĻŦ) āĻĻā§āϝāĻŧā§āĻāĻžāĻ āĻāϞā§āϞā§āĻ āĻāĻā§āĨ¤
āϏā§āϝāĻŧā§āĻšā§, Velocity = Vector Quantity
7. A car changes its velocity from 10 m/s to 20 m/s in 5 s. Its acceleration is: (ā§. āĻāĻāύ āĻāĻžāĻĄāĻŧā§ā§° āĻŦā§āĻ 10 m/s ā§° āĻĒā§°āĻž 20 m/s āĻšāϝāĻŧ 5 s āϤāĨ¤ āϤā§āĻŦā§°āĻŖ āĻāĻŋāĻŽāĻžāύ ?)
(a) 1 m/s² (b) 2 m/s² (c) 5 m/s² (d) 10 m/s²
Ans / āĻāϤā§āϤ⧰: (b) 2 m/s²
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Formula / āϏā§āϤā§ā§° : Acceleration = Change in Velocity / Time Acceleration = (20 − 10) ÷ 5 = 2 m/s²
8. If an object moves with constant velocity, its acceleration is: (ā§Ž. āϝāĻĻāĻŋ āĻā§āύ⧠āĻŦāϏā§āϤ⧠āϏā§āĻĨāĻŋā§° āĻŦā§āĻā§ āĻāϤāĻŋ āĻā§°ā§, āϤā§āύā§āϤ⧠āϤāĻžā§° āϤā§āĻŦā§°āĻŖ āĻāĻŋāĻŽāĻžāύ ?)
(a) 1 m/s² (b) Infinite (c) Zero (d) Negative
Ans / āĻāϤā§āϤ⧰: (c) Zero
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Acceleration is the change in velocity. If velocity remains constant (does not change), then there is no acceleration.
āĻŦā§āϝāĻžāĻā§āϝāĻž: āϤā§āĻŦā§°āĻŖ āĻšā§āĻā§ āĻŦā§āĻā§° āĻĒā§°āĻŋāĻŦā§°ā§āϤāύ⧰ āĻšāĻžā§°āĨ¤ āϝāĻĻāĻŋ āĻŦā§āĻ āϏā§āĻĨāĻŋā§° āĻĨāĻžāĻā§ (āϏāϞāύāĻŋ āύāĻšāϝāĻŧ), āϤā§āύā§āϤ⧠āĻā§āύ⧠āϤā§āĻŦā§°āĻŖ āύāĻžāĻĨāĻžāĻā§āĨ¤ Therefore / āϏā§āϝāĻŧā§āĻšā§, Acceleration = 0 (Zero).
Example / āĻāĻĻāĻžāĻšā§°āĻŖ: A car moves at 20 m/s east all the time. Its velocity does not change.
Acceleration = 0 m/s².
9. Which quantity requires direction ? (⧝. āϤāϞ⧰ āĻā§āύāĻā§ ā§°āĻžāĻļāĻŋā§° āĻŦāĻžāĻŦā§ āĻĻāĻŋāĻļā§° āĻĒā§ā§°āϝāĻŧā§āĻāύ ?)
(a) Distance (b) Speed (c) Velocity (d) Time
Ans / āĻāϤā§āϤ⧰: (c) Velocity
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: Velocity requires direction because it tells us how fast an object is moving and in which direction. Ex: 30 km/h north, Without direction, it is only speed, not velocity.
āĻŦā§āϝāĻžāĻā§āϝāĻž: āĻŦā§āĻ (Velocity) ā§° āĻŦāĻžāĻŦā§ āĻĻāĻŋāĻļā§° āĻĒā§ā§°āϝāĻŧā§āĻāύ āĻšāϝāĻŧ, āĻāĻžā§°āĻŖ āĻ āĻāĻŽāĻžāĻ āĻāϝāĻŧ āĻŦāϏā§āϤ⧠āĻāĻāĻž āĻāĻŋāĻŽāĻžāύ āĻĻā§ā§°ā§āϤ āĻā§°ā§ āĻā§āύ āĻĻāĻŋāĻļāϤ āĻāϤāĻŋ āĻā§°āĻŋāĻā§āĨ¤ āĻāĻĻāĻžāĻšā§°āĻŖ: 30 km/h āĻāϤā§āϤ⧰ āĻĻāĻŋāĻļā§
āĻĻāĻŋāĻļ āĻāϞā§āϞā§āĻ āύāĻžāĻĨāĻžāĻāĻŋāϞ⧠āĻ āĻā§ā§ąāϞ āĻĻā§ā§°ā§āϤāĻŋ (Speed) āĻš'āĻŦ, āĻŦā§āĻ (Velocity) āύāĻšāϝāĻŧāĨ¤
Trick / āĻā§āĻļāϞ: Direction needed → Velocity {āĻĻāĻŋāĻļ āϞāĻžāĻāĻŋāĻŦ → Velocity (āĻŦā§āĻ)}
10. A bike moving at 50 km/h north is an example of: (ā§§ā§Ļ. āĻāĻāύ āĻŦāĻžāĻāĻ 50 km/h āĻŦā§āĻā§ āĻāϤā§āϤ⧰ āĻĻāĻŋāĻļāϞ⧠āĻāϤāĻŋ āĻā§°āĻŋāĻā§āĨ¤ āĻ āĻāĻŋ ?)
(a) Speed (b) Distance (c) Velocity (d) Acceleration
Ans / āĻāϤā§āϤ⧰: (c) Velocity
Explanation / āĻŦā§āϝāĻžāĻā§āϝāĻž: North direction is given. Therefore, it is velocity. (āĻāϤā§āϤ⧰ āĻĻāĻŋāĻļ āĻāϞā§āϞā§āĻ āĻā§°āĻž āĻšā§āĻā§āĨ¤ āϏā§āϝāĻŧā§ āĻ āĻŦā§āĻ (Velocity)āĨ¤)