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Question
Distinguish between speed and velocity.
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Solution
| Speed | Velocity | |
|
1. |
Speed is simply the rate of change of motion. or simply, it is the distance travelled by a body in a unit of time. |
Velocity is direction-aware, and it is the rate of change of position of an object. |
| 2. | Speed is a scalar quantity, i.e. it has only magnitude. | Velocity is a vector quantity, i.e. it has both magnitude and direction. |
| 3. | Speed measures the distance travelled (d) over the change in time (Δt). | Velocity measures displacement (or change in position, Δs) over the change in time (Δt). |
|
4. |
Speed = `"Distance"/"time"` = dt |
Velocity = `"Displacement"/"Time"` = st |
| 5. | Speed ascertains how fast a body moves. | Velocity ascertains the object's speed and the direction it takes while moving. |
|
6. |
Example: A person is making a roundabout journey at a speed of 30 mph. |
Example: A woman plans to drive her car at 56 mph in East Mumbai. |
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