A ship sets sail from Rotterdam, The Netherlands, heading due north at 7.00 m/s relative to the water. The local ocean current is 1.50 m/s in a direction 40.0° north of
east. What is the velocity of the ship relative to the Earth?
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Explanation:

North velocity 7.00 + 1.50sin40 = 7.964 m/s

East velocity 1.50cos40 = 1.149 m/s

v = √(7.964² + 1.149²) = 8.05 m/s

θ = arctan(1.149/7.964) = 8.21° E of N

f=ma a/f/m a= 480/60 a = 8m/s/s that is quick wow

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.