# Homework Help: F=ma and momentum question

1. Jun 6, 2012

### Nitrate

1. The problem statement, all variables and given/known data

Use the concepts of momentum and Newton’s second law to explain why a motorcycle can accelerate at a greater rate than a large truck.

2. Relevant equations

3. The attempt at a solution

The motorcycle will accelerate at a greater rate because the truck has a greater mass (greater resistance to a change in speed.) This increased rate of acceleration is mathematically proven by the formula a= F/m, which states acceleration is inversely proportional to the mass. In terms of momentum, a mass that experiences a change in velocity (acceleration) has undergone a change in momentum (impulse). As the mass of the motorcycle is smaller, it will take less force and time to move it, thus increasing it's rate of acceleration.

2. Jun 7, 2012

### Andrew Mason

You are correct that a = F/m and that the mass of the truck is much greater than the motorcycle. But it also has a bigger engine that can provide a much greater force to the wheels than the small motorcycle engine. So I think you have to deal with the relative engine power.

You could, for example, find out how engine power or torque compares between a motorcycle and a truck and then compare the relative masses.

AM

3. Jun 7, 2012