This problem asks about how the acceleration of car could be increased from 8.40 mi/h·s depending on changes to the net force applied and the car's mass.
Anytime we have a problem asking about force, mass, and acceleration (and only those quantities), we'll use Newton's 2nd Law, often written as
For some problems, we'll want it in a different form, solved for a:
Notice that acceleration is directly proportional to net force and inversely proportional to mass.
A young woman buys an inexpensive used car for stock car racing. It can attain highway speed with an acceleration of 8.40 mi/(h·s). By making changes to its engine, she can increase the net horizontal force on the car by 24.0%. With much less expense, she can remove material from the body of the car to decrease its mass by 24.0%.
(a) Which of these two changes, if either, will result in the greater increase in the car’s acceleration?
(b) If she makes both changes, what acceleration can she attain?
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Newton's 3 Laws concept. If you need more Newton's 3 Laws practice, you can also practice Newton's 3 Laws practice problems.