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 frequency of the photon is 
.
Explanation:
Given that,
Energy 
We need to calculate the energy
Using relation of energy
Where, 
= energy spacing
Put the value of h into the formula
Hence, The frequency of the photon is .
Answer:
Explanation:
given,
cyclist ride 6.2 km east and then 9.28 km in the direction of 27.27° west of north and then 7.99 km west.
vertical component = 9.28 cos∅
= 9.28 cos 27.27°
= 8.24 km
horizontal axis component = 9.28 sin ∅
= 9.28 sin 27.27°
= 4.5 km
distance of the final point from the origin
= 7.99 -(6.2-4.5)
= 6.29 km
displacement
d = 10.37 km
b) 
θ = 37.36°
The total capacitance of two 15uF capacitors connected in parallel is <em>30 μF</em> .
question one b
question 2 i think a
3 d
4 c
5 not sure but wanting to say d
6 letter b
7 not sure
8 idk
9 i have no idea
