Which object is accelerating?

⦁ A car traveling at a constant velocity around an oval shaped track.

⦁ A bicycle slowing down as it goes up a steep hill.

⦁ A skate border speeding up as he skates down a ramp.

⦁ All of the above.

Q. Which object is accelerating?

A: A skateboarder speeding up as he skates down a ramp.

The car is not accelerating as it is travelling at constant velocity. Acceleration refers to the rate of change of velocity of an object over time. Thus, there is no acceleration for the car.

The bicycle is not accelerating as it is decelerating (slowing down). This is not to be confused with accelerating in the opposite direction. Deceleration refers to the rate at which an object slows down. Deceleration is a scalar quantity whereas acceleration is a vector quantity. Yeah.

The final one isn't right, well, because the first two options are wrong.

So through process of elimination, you can deduce that the skateboarder experiences acceleration.

Also, the skateboarder experiences acceleration as he is "speeding up", implying that his speed is not constant and in fact increasing, so there's acceleration.