Help with a physics TEST (im desperate)

AI Thread Summary
A 14-year-old student from Bulgaria is seeking help for a physics test, specifically regarding a problem involving a moving body weighing 4 kg with a displacement equation. The student has calculated most exercises but is struggling with determining the velocity and force from the given displacement formula. A forum member explains that the displacement equation resembles a kinematic motion equation, indicating constant acceleration, and suggests that additional information is needed to solve the problem completely. They clarify the difference between force and power, emphasizing that power is calculated as the product of instantaneous force and velocity. The discussion highlights the importance of understanding basic physics concepts to solve the problem effectively.
Killvenom
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First of all Hi!
Im from Bulgaria (Europe for the ones who don't know where BG is) and I am new to the forum
Im 14 and I've started learning physics in german (i learn in a german high school..)
I might have a bit of mistakes /mainly spelling/ so please excuse me for them...
So tommorow I am having a physics test and a friend made a photo of it
I calculeted most of the exercises but this one i didnt

Its easy perhaps (for you) but not for me:
For the guys who speak german
[Removed German. As per the forum guidelines, all posts must be in English]

For English speakers
A body is moving and weighs 4kg and s = 4t - 4.squaret
The movement type is
V=??
The whole Force (power) is ? N
 
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Killvenom

Welcome to PF!

Your formula for displacement, s, is in the form of the basic kinematic motion equation with constant acceleration, that is, s = V_ot +1/2at^2. From this you can get certain information. You need more given information to get all the requested information. The net force can be obtained from Newton's 2nd law.
 
force isn't power. Power = Instantaneous force x velocity

P = Fv
 

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