The Vector Nature of Newton's Second Law

AI Thread Summary
The discussion centers on calculating the acceleration of a 2.0kg block on a frictionless inclined plane at a 15-degree angle. The force of gravity acting on the block is 20N, and the relevant formula involves the component of gravitational force acting parallel to the incline, which is mgsin(theta). Participants clarify that since the plane is smooth, there is no friction to consider in the calculations. A mistake was acknowledged regarding the use of the wrong formula component, emphasizing the importance of using the correct sine function for the incline. The conversation highlights the need for careful attention to detail in physics problems involving vector forces.
thomasrules
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A block of mass 2.0kg is placed on a smooth plane, inclined to the horizontal at an angle of 15degrees. The force of gravity, acting straight down on the block, is 20N.
a) What is the acceleration of the block down the plane?

I'm having trouble with this because I know:
Net F=fgcostheta-friction
or fgcostheta-friction=ma=2a

BUT THERE IS NO FRICTION GIVEN NOR A COEFFICIENT OF FRICTION

If anyone knows the answer please share

THanks
 
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Of course you don't have a coefficient of friction. A smooth plane implies no friction! Also, the component of the weight acting parallel to the plane is mgsin theta.
 
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Ya I'm a real dumbass I also made a 2 other dumb mistakes...i used fgcostheta instead of fgsintheta...THANKS ANYWAY ! grrrrrrrrrrrrrrrrrrrr
 

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