I wouldn't consider it construction
An idea that is supported by some evidence, but is not yet the basis for a field of study is called a working theories.
<u>Explanation:
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The combined form of one’s skills, the work experiences from testing to reveal some truth about the issues or being involved one’s work in an experiment usually called as working theory.
These type of theories are more elaborate, interconnected, make some experiences with the solution to sort out the issues and seems to be useful in event monitoring. These can be supported with certain evidences but still not acting as the basement for the field study.
<span>11.25 kg of sand.
The coefficient of static friction tells you what fraction of the normal force is needed to start the object moving. Since the block is on a horizontal surface, the normal force is the same as the mass of the block. Therefore
M = 28 * 0.450 = 12.60
So once the mass hanging off the cord reaches 12.60 kg, the block will start to move. And since the bucket masses 1.35 kg, you need to subtract the mass of the bucket from the total mass needed, giving
M = 12.60 - 1.35 = 11.25</span>
Displacement and distance are two different things, distance is the total distance traveled, this would be easy in the case of the ant, that would simply be 15+25= 40cm.
But, displacement is the 'birds eye' distance between two points, in this question it can be worked out using Pythagoras. (there is a right angled triangle) imagine the base of this triangle is the east direction and north being the upright. then the displacement would be the largest side of the triangle, or the hypotenuse.
Pythagoras said that A^2 + B^2 = C^2
where C is the hypotenuse.
so 15^2 + 25^2 = C^2
C^2 =850
simply square root this to get C
sqrt(850) = 29.15 cm
29.15 cm displaced by the ant
Remaining Distance = 180miles-90miles= 90miles
Time taken for first part of her journey= 90miles / 30miles/h= 3hours
To have average speed of 40mph,
Let the time taken for second part be xh
180 / 3h+xh =40
3+x= 4.5h
x =1.5h
Constant speed she must drive = 90miles / 1.5h = 60mph