B
Assume north and east as two sides of a right angled triangle. magnitude of the distance is then given by the length of the hypotenuse which is 
where a = 1.2 km north
and b = 1.6 km east
magnitude = 2 km
Direction is given by the angle between them, that is atan(a/b) = 36.86 deg north of east = 53.1 deg east of north.
Answer:7 cm/s
Explanation:
Given
Particle move along curve

As it reaches the (2,3) its y coordinate is increasing at 14 cm/s
Differentiating y w.r.t time
Now at (2,3)

Answer:
Waves. Refraction is an effect that occurs when a light wave, incident at an angle away from the normal, passes a boundary from one medium into another in which there is a change in velocity of the light. ... The wavelength decreases as the light enters the medium and the light wave changes direction.
Explanation:
As a wavelength increases in size, its frequency and energy (E) decrease. From these equations you may realize that as the frequency increases, the wavelength gets shorter. ... Mechanical and electromagnetic waves with long wavelengths contain less energy than waves with short wavelengths.
Use the eq. of Young modulus Y=(F/A)/(∆l/lo)
dimana ∆l is the elongation of wire, lo is its initial length.
So ∆l = (F/A)lo/Y.
∆l = (1000N/(6.5 × 10^-7 m^2))×(2.5m)/(2.0 × 10^-11 N/m^2)
Use calculator to finish it.
Newton’s second law gives us the relationship of force F,
mass m and acceleration a. The formula is given as:
<span>F = m a -->
1</span>
However we also know that the relationship of mass m,
density ρ, and volume V is:
<span>m = V ρ -->
2</span>
Therefore substituting equation 2 to equation 1:
F = ρ V a = ρ V g
where a is acceleration due to gravity, ρ is density of
water and V is the volume of the casting, therefore:
F = (1x10^-3 kg/cm^3) (4840 cm^3) (9.8 m/s^2)
F = 47.432 kg m/s^2
F = 47.432 N
Going back to equation 1:
47.432 N = m (9.8 m/s^2)
m = 4.84 kg
<span>Hence the weight of the final casting is 4.84 kg</span>