Your roommate is working on his bicycle and has the bike upside down. He spins the 68.0cm -diameter wheel, and you notice that a pebble stuck in the tread goes by three times every second.
What is the pebble's speed?
What is the pebble's acceleration?
speed=distance/time=PI*68cm/.3333sec
acceleration= speed^2/radius
of course, radius is still half diameter.
2-5
To determine the pebble's speed and acceleration, we can use the information provided and some basic physics principles.
1. Pebble's speed:
The speed of the pebble can be calculated using the formula: Speed = Distance / Time.
In this case, the distance is equal to the circumference of the wheel, which is given by the formula: Circumference = π × diameter.
So, the circumference of the wheel is π × 68.0cm.
Since the pebble goes by three times every second, the time is 1 second / 3.
Now we have all the values needed to calculate the speed:
Speed = (π × 68.0cm) / (1 second / 3)
Speed = (π × 68.0cm) × 3
Speed ≈ 202.62 cm/s
Therefore, the pebble's speed is approximately 202.62 cm/s.
2. Pebble's acceleration:
To determine the pebble's acceleration, we need to know the change in speed over time. However, based on the given information, we don't have any data about the change in speed. Therefore, we cannot calculate the acceleration.
In summary:
The pebble's speed is approximately 202.62 cm/s.
The pebble's acceleration cannot be determined with the given information.