The working equation for this one is:
E = F/Q, where E is the strength of the electric field, F is the electric force and Q is the charge. Substituting the corresponding values, the strength of the electric field is equal to
E = -30 nN/-3 nC
E = 10 nN/nC
The resultant motion is given by pithagoras, since the two components (north and east) are perpendicular to each other.
They are asking you about the direction so you have to use trigonometry, finding that the direction is Ф=arctan(3.8/12)=17.57° north of east.
Answer:
<em>a) Fvt cosθ</em>
<em>b) Fv cosθ</em>
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Explanation:
Each horse exerts a force = F
the rope is inclined at an angle = θ
speed of each horse = v
a) In time t, the distance traveled d = speed x time
i.e d = v x t = vt
also, the resultant force = F cosθ
Work done W = force x distance
W = F cosθ x vt = <em>Fvt cosθ</em>
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b) Power provided by the horse P = force x speed
P = F cosθ x v
P = <em>Fv cosθ</em>