Mechanics & physics,can anyone explain the scenarios?Very practical Questions?

AI Thread Summary
The discussion revolves around a request for explanations of various physics and mechanics scenarios related to a mechanical aptitude test. The original poster has provided answers to several questions but seeks theoretical backing for their responses. Key points include the relationship between torque and distance from the center of rotation, the properties of magnetic fields, and thermal insulation comparisons. The poster also expresses uncertainty about some answers, particularly regarding questions four, seven, and nine. Overall, the thread emphasizes the need for clarity in understanding the underlying principles of physics.
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Mechanics & physics,can anyone please explain the scenarios?Very practical Questions?

Hi...Can anyone please be kind enough to help me? i know it will take a bit longer for u to answer. I have some scenarios and questions in the following pages:

http://www.geocities.com/flabberguest_gabcraft/pg1.jpg
http://www.geocities.com/flabberguest_gabcraft/pg2.jpg

These are related to physics & mechanical aptitude test. I know the answers but i am not able to explain them with the help of theories. Can anyone please help me explain these situations. Please take a look it is interesting thanks in advance ...
for assistance I'm providing the Answers:
Q1 = A
Q2 = B
Q3 = A
Q4 = don't know
Q5 = A
Q6 = B
Q7 = don't know
Q8 = B
Q9 = don't know
 
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I think that Q4 = C because the the magnetic field which is induced by the current flowing in the wire is not in any of the direction described in A or B (It is actually normal to the plane of the screen.
Also, Q3 = A because the torque of a force acting at a larger distance from the center of rotation is larger than one acting close to the center, that is torque = F x r where r is the distance from the center and x is a cross product.
Also Q8=B because saw dust is more thermally insulating than air, I suppose.
 


Question 9 is A since three points define a plane. More than that and you will have at least one leg off the floor on uneven ground.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
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