How Do You Calculate Acceleration and Speed of a Block on an Incline?

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To calculate the acceleration of a block sliding down an incline at a 22-degree angle, use the formula for gravitational force component parallel to the incline, which is g*sin(22). The acceleration can be determined as "gsin22," where g is the acceleration due to gravity. To find the block's speed at the bottom after sliding 9.10m from rest, apply the kinematic equation V^2 = U^2 + 2a*s, substituting the initial velocity (U) as zero and using the calculated acceleration (a). The mass of the block is irrelevant in this scenario, as it cancels out in the equations. Properly drawing the free body diagram and applying trigonometric principles is essential for accurate calculations.
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I need help with the following problem:

The block shown in fig 4-48 lies on a smooth plane tilted at an angle 22 degrees to the horizontal. (a)Determine the acceleration of the block as it slides down the plane. (b) If the block starts from rest 9.10m up the plane from its base, what will be the block's speed when it reaches the bottom of the incline? I'll attach a paint picture of the diagram I have. I really need help with part a, so if you are strapped for time I would really appreciate it if you could help me with a, I'm pretty sure I could figure out b. Btw it also says Ignore friction and that the coefficient of friction is .20 between the block and the incline plane. In the picture that I have attached I've also drawn what I think the free body diagram for this problem is, please correct it if it is wrong. It says nothing about the mass of the block so I am pretty sure some substituting formulas is going to be done and that's where I am having problems.
 

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on your digram use the bit on the left to work out (using trig) what the component of force acts parallel to the incline. So you know the force, find the acceleration :)

Always work in algebra right until the end, the mass will cancel.
 
Acceleration down the plane is "gsin22"
to calculate speed at the bottom,
V^2 = U^2 + 2a*s U initial velocity s distance covered
 
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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