ellieee
- 78
- 6
- Homework Statement
- nil
- Relevant Equations
- nil
qn3: why is statement 2 the only answer? isn't speed one of the factors in velocity too? then shouldn't statement 1 be true too?
When an object is accelerating, does speed, velocity, or force change?
- Thread starter ellieee
- Start date
-
- Tags
- Accelerating Change Force Speed Velocity
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 1K views
qn3: why is statement 2 the only answer? isn't speed one of the factors in velocity too? then shouldn't statement 1 be true too?
Velocity can change without speed changing. This occurs in circular motion, where the velocity vector changes continuously while speed is held constant. Examples include a tetherball on a string, a car going around a curve at a constant speed, and an object in a circular orbit.
Gold Member
- 2,843
- 2,566
You have to remember that in physics and maths, acceleration means:
1. speeding up or
2. slowing down or
3. changing direction
(or a mixture of 1&3 or 2&3).
That's because velocity is a vector (has magnitude and direction) and acceleration is how fast velocity changes.
(This is different to the non-scientific use of the word 'acceleration' which simply means speeding up.)
So, as @Drakkith notes, for something going in a circle at a steady speed, the velocity is changing (as the direction of velocity is constantly changing). This is classified as 'acceleration'.
1. speeding up or
2. slowing down or
3. changing direction
(or a mixture of 1&3 or 2&3).
That's because velocity is a vector (has magnitude and direction) and acceleration is how fast velocity changes.
(This is different to the non-scientific use of the word 'acceleration' which simply means speeding up.)
So, as @Drakkith notes, for something going in a circle at a steady speed, the velocity is changing (as the direction of velocity is constantly changing). This is classified as 'acceleration'.