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    I was doing a past paper (multiple choice) and it had a question that asked about the impact of constant force on the speed of a car. Since it is constant force, it implies that there is net acceleration, which implies that the speed is constantly changing. Thus, shouldn't the speed-time graph for a net force acting on the car be a concave upwards graph like this? : (see image below)

    To my surprise, the correct graph says that the speed is a straight line (y=mx+c) which in my opinion should be a velocity-time graph.

    Please help me grasp the concept better
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    (Original post by Annie18451)
    I was doing a past paper (multiple choice) and it had a question that asked about the impact of constant force on the speed of a car. Since it is constant force, it implies that there is net acceleration, which implies that the speed is constantly changing. Thus, shouldn't the speed-time graph for a net force acting on the car be a concave upwards graph like this? : (see image below)

    To my surprise, the correct graph says that the speed is a straight line (y=mx+c) which in my opinion should be a velocity-time graph.

    Please help me grasp the concept better
    The force is constant, meaning the acceleration is also constant. Acceleration is the gradient on a velocity-time graph meaning the gradient is constant, and hence the graph is a straight line


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    (Original post by Kyx)
    The force is constant, meaning the acceleration is also constant. Acceleration is the gradient on a velocity-time graph meaning the gradient is constant, and hence the graph is a straight line


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    Thanks! I just realised I made a silly mistake. I accidentally took it to be a displacement-time graph instead of a speed-time graph
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    (Original post by Annie18451)
    Thanks! I just realised I made a silly mistake. I accidentally took it to be a displacement-time graph instead of a speed-time graph
    Hehehe no problem


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