Answer:
Dy = - 0.0789 [m]
Explanation:
The vertical component of the vector can be determined with the sine of the angle.
Dy = 0.250*sin(18.4)
Dy = 0.0789 [m]
As the y-component is pointing downwards the component is negative.
Dy = - 0.0789 [m]
(a) For the work-energy theorem, the work done to lift the can of paint is equal to the gravitational potential energy gained by it, therefore it is equal to

where m=3.4 kg is the mass of the can, g=9.81 m/s^2 is the gravitational acceleration and
is the variation of height. Substituting the numbers into the formula, we find

(b) In this case, the work done is zero. In fact, we know from its definition that the work done on an object is equal to the product between the force applied F and the displacement:

However, in this case there is no displacement, so d=0 and W=0, therefore the work done to hold the can stationary is zero.
(c) In this case, the work done is negative, because the work to lower the can back to the ground is done by the force of gravity, which pushes downward. Its value is given by the same formula used in part (a):

Answer:
The value is 
Explanation:
From the question we are told that
The first amplitude of the wave is 
The first depth is 
The second amplitude is
The second depth is 
Generally from the spatial wave equation we have

=> 
So considering the ratio of the equation for the two depth

=> 
=> 
=> 
The answer is donate, therefore elements with positive valences usually donate electrons
Answer:
its true that Scientific endeavor is driven by both simple curiosity as well as societal demands.
Explanation:
When a scientist has a curiosity about something he carried out a research. and when their is a demand of something in society that time scientific research is carried out. Therefore its true that a scientific endeavor is driven by simple curiosity or societal demand.
For example
in society, there is demand of a medicine which can completely kill the cancer and a scientist has curiosity to know how to kill cancer cell. In this way a scientific endeavor for cancer medicine can be carried out by both simple curiosity as well as societal demands.