Answer:
The given vector can be represented in unit vector as

The magnitude of any vector
is given by

Applying values we get

We know that positive x axis in vertorial form is represented as

taking dot product of both the vector's we get

Answer:

Explanation:
As we know that the charge per unit length of the long cylinder is given as

here we know that the electric field between two cylinders is given by

now we know that electric potential and electric field is related to each other as





Lithium has an atomic number of 3 so right away all the answer choices are eliminated except A., and oxygen does have 8 neutrons, boron 5 electrons, and neon a mass of 20
Answer:
Explanation:
A proton and electron are moving in the positive x direction, this shows that their velocity will be in the positive x direction
V = v•i
Magnetic field Is the positive z direction
B = B•k
A. For proton.
Proton has a positive charge of q
Direction of force on proton
Force is given as
F = q(v×B)
F = q( v•i × B•k)
F = qvB (i×k)
From vectors i×k = -j
F = -qvB •j
Then, for the positive charge, the force will act in the negative direction of the y-axis
B. For electron
Electron has a negative of -q
Direction of force on proton
Force is given as
F = q(v×B)
F = -q( v•i × B•k)
F = -qvB (i×k)
From vectors i×k = -j
F = --qvB •j
F = qvB •j
Then, for the negative charge, the force will act in the positive direction of the y-axis