Answer:
Explanation:
There are two hypotheses she could test:
A cat's heart rate changes while it is napping.
A cat's heart rate does not change while it is napping.
The right answer for the question that is being asked and shown above is that: "A.tectonic activity concentrated in certain areas." A piece of evidence did Alfred Wegener use to develop the theory of continental drift is that <span>A.tectonic activity concentrated in certain areas</span>
Answer:
56°
Explanation:
Brewsters angle can be simply derived from
n1sin theta1= n2sintheta2= n2costheta1
because the reflected light will be 100% polarized if it is reflected at an angle 90o to the refracted light. Hence, Brewsters angle is
Tan theta= n2/n1
1.66/1.11= 1.495
Theta = 56°
Explanation:
1) In an uniformly accelerated motion, the acceleration is given by:

where

is the final speed,

is the initial speed, and

is the time interval between the initial and final point of the motion.
Using the data of the problem:

,

, and the time

, the acceleration is

where the negative sign means that the hockey puck is decelerating.
2) The frictional force F between the puck and ice is responsible for the deceleration of the puck, and for second Newton's law this force is equal to the product between the mass of the puck m and the acceleration:

(1)
The frictional force can also be written as

(2)
where

is the coefficient of kinetic friction, and where the negative sign is due to the fact that the frictional force acts against the direction of motion of the puck. By equilizing (1) and (2) we can find the value of this coefficient:
