Acceleration: is this accelerating?

[emma402]

Which of the following objects is accelerating:

1. A motorcycle rounds a curve without changing speed.
2. A helicopter ascending straight upward without speeding up for slowing down.
3. A person jogging straight south at a constant speed.
4. A bus starts moving after waiting for a stoplight, traveling in a straight line.
5. A car speeds up while driving east along a level road.
6. A car drives at a constant 45mph as it goes over the top of a hill

What I think as solutions...(correct me please if I'm wrong)

1. yes 4.yes
2. no 5.yes
3. no 6.yes

 

[White Noise]

For this all you need to know - as I'm sure you do - is that any change in velocity means there is acceleration.

So yes, each of your answers are correct, in short.

 

[Fallinleave]

those are great questions.