Answer:
F = - k (x-xo) a graph of the weight or applied force against the elongation obtaining a line already proves Hooke's law.
Explanation:
The student wants to prove hooke's law which has the form
F = - k (x-xo)
To do this we hang the spring in a vertical position and mark the equilibrium position on a tape measure, to simplify the calculations we can make this point zero by placing our reference system in this position.
Now for a series of known masses let's get them one by one and measure the spring elongation, building a table of weight vs elongation,
we must be careful when hanging the weights so as not to create oscillations in the spring
we look for the mass of each weight
W = mg
m = W / g
and we write them in a new column, we make a graph of the weight or applied force against the elongation and it should give a straight line; the slope of this line is sought, which is the spring constant.
The fact of obtaining a line already proves Hooke's law.
Explanation:
It is given that,
Velocity in East, 
Velocity in North, 
(a) The resultant velocity is given by :

(b) The width of the river is, d = 80 m
Let t is the time taken by the boat to travel shore to shore. So,


t = 16 seconds
(c) Let x is the distance covered by the boat to reach the opposite shore. So,


x = 48 meters
Hence, this is the required solution.
Answer:
1. B
2. B
Explanation:
1. he was the only teacher at that time that figured out that everything doesn't revolve around us. he figured it out by a telscope he made from three lens and a tube. its actually pretty cool. He found out that venus first was in front of us.
2. if the earth wasn't at a tilt, then we wouldn't have sessons, when the earth rotate around the sun, the earth is roataing at a title axis. and that changes our seesons, because if we are in south america, and we are in winter time, and south america is cold, then it means that the continent is not getting as much heat from the sun. Does that makes since, because it doesn't sound like it?