Construct a vector diagram. It will be a right-angled triangle. One vector (the hypotenuse) represents the heading of the boat, one represents the current and one represents the resultant speed of the boat, which I'll call x. Their magnitudes are 20, 3 and x. Let the required angle = theta. We have:
<span>theta = arcsin(3/20) = approx. 8.63° </span>
<span>The boat should head against the current in a direction approx. 8.63° to the line connecting the dock with the point opposite, or approx. 81.37° to the shore line. </span>
<span>x = sqrt(20^2 - 3^2) </span>
<span>= sqrt(400 - 9) </span>
<span>= sqrt 391 </span>
<span>The boat's crossing time = </span>
<span>0.5 km/(sqrt 391 km/hr) </span>
<span>= (0.5/sqrt 391) hr </span>
<span>= approx. 0.025 hr </span>
<span>= approx. 91 seconds</span>
Answer:
The force is 
Explanation:
The diagram for this question is shown on the first uploaded image
At Equilibrium the summation of the of force on the vertical axis is zero
i.e 
=> 
is the is the speed of water at the nozzle which can be mathematically evaluated as

substituting
for R and
for


is the is the speed of water at the pipe which can be mathematically evaluated as

substituting
for R and
for


is he density of water with value 
Substituting values into the equation above


At Equilibrium the summation of the of force on the horizontal axis is zero
i.e 
=> 
Since The speed at both A and B nozzle are the same then
remains the same
Substituting values

=> 
Hence the force acting on the flange bolts required to hold the nozzle in place is



Answer:
The initial acceleration of the 59g particle is
Explanation:
Newton's second laws relates acceleration (a), net force(F) and mass (m) in the next way:
(1)
We already know the mass of the particle so we should find the electric force on it to use on (1), the magnitude of the electric force between two charged objects by Columb's law is:

with q1 and q2 the charge of the particles, r the distance between them and k the constant
. So:

Using that value on (1) and solving for a

Answer;
-it will move away from the large ball because like charges repel.
Explanation;
-Electric force is the force that pushes apart two like charges, or that pulls together two unlike charges. The basic law of electrostatics Like charges of electricity repel each other, whereas unlike charges attract each other.
When small, positively charged ball is moved close to a large, positively charged ball it would be pushed away from the large positively charged ball since they are both positively charged. One has to put in energy to try to move the small ball closer to the large ball. The closer one try to move it to the large ball, the more energy one has to put in, so the more electrical potential energy the small ball would have.