Solving Forces and Motion Problem: Find Net Force at t=2.35s

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To find the net force acting on a 3.45 kg object at t = 2.35 s, the object's acceleration must first be determined from its position equations x = 7t² - 3 and y = 4t³ + 3. By calculating the second derivatives of the position functions, the acceleration in both the x and y directions can be found. Applying Newton's second law (F = ma), the net force can then be calculated using the mass and the resultant acceleration. The final result will provide the magnitude of the net force at the specified time. Understanding these steps is crucial for solving similar forces and motion problems.
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Hi,

I am trying to help my brother do this problem but I can't figure it out! can anyone please help me...


A 3.45 kg object is moving in a plane, with its x and y coordinates given by x = 7t² - 3 and y = 4t³ + 3, where x and y are in meters and t is in seconds. Find the magnitude of the net force acting on this object at t = 2.35 s.

thank you so much
 
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Hint: Newton's 2nd law.
 
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