Answer:

Explanation:
The total force on the particle is given by

Then, by replacing we have:
![q\vec{v}\ X \vec{B}=q[7\hat{k}-9\hat{j}-\hat{k}]\\\\q\vec{E}=q[5\hat{i}-\hat{j}-2\hat{k}]\\\\\vec{F}=(9.61*10^{-19}C)[(7+9)\hat{i}+(-9-1)\hat{j}+(-1-2)\hat{k}]\\\\\vec{F}=(1.537*10^{-17}\hat{i}-9.61*10^{-19}\hat{j}-2.883*10^{-18}\hat{k})N](https://tex.z-dn.net/?f=q%5Cvec%7Bv%7D%5C%20X%20%5Cvec%7BB%7D%3Dq%5B7%5Chat%7Bk%7D-9%5Chat%7Bj%7D-%5Chat%7Bk%7D%5D%5C%5C%5C%5Cq%5Cvec%7BE%7D%3Dq%5B5%5Chat%7Bi%7D-%5Chat%7Bj%7D-2%5Chat%7Bk%7D%5D%5C%5C%5C%5C%5Cvec%7BF%7D%3D%289.61%2A10%5E%7B-19%7DC%29%5B%287%2B9%29%5Chat%7Bi%7D%2B%28-9-1%29%5Chat%7Bj%7D%2B%28-1-2%29%5Chat%7Bk%7D%5D%5C%5C%5C%5C%5Cvec%7BF%7D%3D%281.537%2A10%5E%7B-17%7D%5Chat%7Bi%7D-9.61%2A10%5E%7B-19%7D%5Chat%7Bj%7D-2.883%2A10%5E%7B-18%7D%5Chat%7Bk%7D%29N)
where the cross product can be made with the determinant method.
Hope this helps!!
Answer:
2271.16N/C upward
Explanation:
The diagram well illustrate all the forces acting on the mass. The weight is acting downward and the force is acting upward in other to balance the weight.since the question says it is motionless, then indeed the forces are balanced.
First we determine the downward weight using

Hence for a mass of 3.82g 0r 0.00382kg we have the weight to be


To calculate the electric field,

Since the charge on the mass is negative, in order to generate upward force, there must be a like charge below it that is repelling it, Hebce we can conclude that the electric field lines are upward.
Hence the magnitude of the electric force is 2271.16N/C and the direction is upward
Answer:
A) The resultant force is 43.4 [N]
B) The movement of the heavy crate is going to the right and in the negative direction on the y-axis
Explanation:
We need to make a sketch of the different forces acting on the heavy crate.
In the attached image we can see the forces and the sum of the vector with their respective angles.
Forces in the X-axis

Forces in the y-axis
![FDiony=0[N]\\Fshirley= 16.5*sin(30)=8.25[N]\\Fjoany=19.5*sin(60)=16.88 [N]\\\\Forcesy=0+8.25-16.88= -8.63[N]](https://tex.z-dn.net/?f=FDiony%3D0%5BN%5D%5C%5CFshirley%3D%2016.5%2Asin%2830%29%3D8.25%5BN%5D%5C%5CFjoany%3D19.5%2Asin%2860%29%3D16.88%20%5BN%5D%5C%5C%5C%5CForcesy%3D0%2B8.25-16.88%3D%20-8.63%5BN%5D)
Using the Pythagorean theorem

The movement of the heavy crate is going to the right and in the negative direction on the y-axis, this can be easily seen in the graphical sum of vectors.