Introductory problem about force (N)

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Homework Help Overview

The problem involves a car with a specified mass accelerating on a flat road, where the net force acting on the car is questioned in the context of opposing resistive forces.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the application of Newton's second law, questioning the relevance of the resistive force in determining the net force. There is an exploration of how to correctly interpret the forces acting on the car.

Discussion Status

Some participants have offered hints regarding the correct approach to calculating the net force, emphasizing the importance of considering all forces acting on the object. There appears to be a productive dialogue about the assumptions made in the problem setup.

Contextual Notes

There is mention of potential confusion introduced by the resistive force value, which some participants suggest may not be necessary for solving the problem as stated.

SamuelVictor
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Homework Statement


A car of mass 1000 kg accelerates on a straight, flat, horizontal road with an acceleration a = 0.3 m s-2 . The driving force F on the car is opposed by a resistive force of 500 N. What is the net (resultant) force on the car?

Homework Equations


F=ma

The Attempt at a Solution


0.3*1000= 300N
500N- 300N= 200N
answer is 300N... Why?
 
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Hint:
To use Newton's second law, F should be the NET force, the sum of all forces
F = m*a retry solving the equation ;)
 
SamuelVictor said:

Homework Statement


A car of mass 1000 kg accelerates on a straight, flat, horizontal road with an acceleration a = 0.3 m s-2 . The driving force F on the car is opposed by a resistive force of 500 N. What is the net (resultant) force on the car?

Homework Equations


F=ma

The Attempt at a Solution


0.3*1000= 300N
500N- 300N= 200N
answer is 300N... Why?

The 500N number is not needed for this problem -- they just threw that into confuse you. The Net Force F is what gives the Net Acceleration a with the car having the Mass m. They ask for the Net Force and give you the Net Acceleration and mass. That's all you need. Makes sense now?
 
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thanks that helps
 

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