Need help finding the relationship between force and acceleration

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The discussion focuses on the relationship between force and acceleration, particularly in the context of a graph depicting oscillating acceleration. The user describes an acceleration graph that oscillates between positive and negative values, leading to confusion about how to represent the corresponding force graph. It is noted that force and acceleration graphs share a similar shape due to Newton's second law (F=ma), where the force is proportional to the acceleration. The conversation also touches on the implications of constant velocity, indicating that both acceleration and force would be zero in that scenario. Overall, understanding the direct relationship between these graphs is crucial for accurately depicting the dynamics of the system.
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Homework Statement



A force is applied that makes an object move with the acceleration shown below. Assuming that friction is negligible, sketch a force-time graph of the force on the object on the axes below.

Since i don't have a scanner. Let me describe the graph of the acceleration. It oscillates from positive 1 to negative 1.5, then to positive two, then negative 1.5 then to positive 1 and evens out. So there are three humps within 5 seconds.

i don't know the relationship between the acceleration graph and force graph so i am stuck here. I know that they have to be in the same direction because 'a force [was] applied that made the object move'. But how will the graph of the force vs time look. Will it just be the derivative of the acceleration graph?
 
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I may be wrong here, but I think Newton came up with a famous equation that relates force to acceleration.
 
well i was looking more for "the accleration is the slope of the velocity graph" but in regards to force and accleration.

another example would be the velocity is the slope of the position graph.

so, if i may add another question: what is the force graph in relation to the acceleration graph. if the velocity graph and acclertaion graph are both constant, that is that they are both horizontal lines; what will the force graph look like?
 
if the velocity is constant, than acc. and force are zero.

Another thing - the graph of force and acceleration (with respect to a common variable, say time) basically have the SAME shape (f=ma, m being a scalar).
Absolute values will change according to the value of mass in the equation above.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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