The discussion revolves around calculating the net force required to accelerate a bike and rider from rest to a specified final velocity over a set time period. The subject area includes concepts from kinematics and Newton's laws of motion.
The discussion is active, with participants providing feedback on each other's reasoning. Some guidance has been offered regarding the correct approach to finding acceleration, and there is a recognition of the need to apply Newton's second law appropriately.
Participants are working under the constraints of a homework problem, which may limit the information available for discussion. There is an emphasis on understanding the definitions and relationships between physical quantities involved.
cepheid said:No. Think about it. If you tried what you are suggesting, your result would have dimensions of [force]/[time], which is not physically meaningful here. You're looking for a force. To get the force, you need to know the acceleration so that you can apply Newton's second law, as you correctly stated. However, you made a mistake. You substituted the velocity (22.7 m/s) in for the acceleration. Velocity is not acceleration -- they are two very different things! I hope you understand how they differ.
In this problem, the acceleration is an unknown. To find it, you will need to consider the kinematics of the problem. ;)
cepheid said:Yeah that looks right to me, provided you assume the acceleration is constant. Acceleration = (change in velocity) / (change in time).