The Earth's Rotational Speed: Where to Stand for Minimum Speed?

AI Thread Summary
To achieve the smallest tangential speed on Earth, one should stand at the poles, where rotational movement is minimal. While it is theoretically possible to design a clock where all hands move at the same tangential speed, practical implementation is hindered by the varying lengths of the hands. If a truck's speedometer measures angular speed and larger tires are fitted, the speedometer will read higher than the actual linear speed due to the increased circumference of the tires. The angular acceleration of a fan's blades cannot be constant while slowing down because the rate of deceleration changes until they stop. Overall, the discussion highlights the complexities of rotational motion and its implications in various scenarios.
hatingphysics
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1) The Earth rotates once per day about its axis. Where on the Earth's surface should you stand in order to have the smallest possible tangential speed?

would it be on the top of axis since it will not move?

2) It is possible, but not very practical, to build a clock in which the tips of the second hand, the minute hand, and the hour hand move with the same tangential speed. Explain why it would be possible but not practical.

I have no idea here...i didn't even know this was possible?!3) Suppose that the speedometer of a truck is set to read the linear speed of the truck, but uses a device that actually measure the angular speed of the tires. If larger diameter tires are mounted on the truck, will the reading of the speedometer be correct? if not, will the reading be greater than or less than the true linear speed of the truck? Why?

No, because the diameter is more for the wheel which will give a larger speed compared to the linear speed. Is this true...i don't know what the right answer is.

4) The blades of a fan rotate more and more slowly after the fan is shut off. Eventually they stop rotating altogether. In such a situation we sometimes assume that the angular acceleration of the blades is constant and apply the equations of rotational kinematics as an approximation. Explain why the angular acceleration can never really be constant in this kind of situation.

is it because the speed of the fan turning off is changing till it stops?

5) Rolling motion is one example that involves rotation about an axis that is not fixed. Give three other examples. In each case, identify the axis of rotation and explain why it is not fixed.

i have no clue!
 
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hatingphysics said:
2) It is possible, but not very practical, to build a clock in which the tips of the second hand, the minute hand, and the hour hand move with the same tangential speed. Explain why it would be possible but not practical.

I have no idea here...i didn't even know this was possible?!
Think of the length of each hand.
 
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