Introductory problem about force (N)

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The problem involves a car with a mass of 1000 kg accelerating at 0.3 m/s². The net force can be calculated using Newton's second law, F = ma, resulting in a net force of 300 N. The resistive force of 500 N is irrelevant for calculating the net force in this context. The confusion arises from the inclusion of the resistive force, which does not affect the calculation of net force when acceleration and mass are provided. Understanding that only the mass and acceleration are needed clarifies the solution.
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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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