You need to use trigonometry to work this one out. The components of the force are needed. it is a vector, so work out the unbalanced force using trig. you know that the force pulling the 5kg skateboard down is going to be 9.8 * 5 = 49N. As you have the angle it is on, and 49 is the vertical component, you can use Sin(X) = Op/Hyp where x= 15 degress, the opposite is the vertical component (49N) and the hyp is the unbalanced force - which is 79.35. I think. Somebody plz double check me on that one though :P
The net force acting on the 5.0 kg skateboard on a 15-degree ramp is approximately 12.66 N, leading to an acceleration of about 2.53 m/s² down the incline. When a 45 kg teenager jumps on, the total mass becomes 50.0 kg, but the acceleration down the ramp remains the same at approximately 2.53 m/s² due to the unchanged incline angle. This shows that, on an incline without friction, the acceleration is independent of mass.
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