Answer:
(a) 7.315 x 10^(-14) N
(b) - 7.315 x 10^(-14) N
Explanation:
As you referred at the final remark, the electron and proton undergo a magnetic force of same magnitude but opposite direction. Using the definition of magnetic force, a cross product must be done. One technique is either calculate the magnitude of the velocity and magnetic field and multiplying by sin (90°), but it is necessary to assure both vectors are perpendicular between each other ( which is not the case) or do directly the cross product dealing with a determinant (which is the most convenient approach), thus,
(a) The electron has a velocity defined as: ![\overrightarrow{v}=(2.4x10^{6} i + 3.6x10^{6} j) \frac{[m]}{[s]}\\\\](https://tex.z-dn.net/?f=%5Coverrightarrow%7Bv%7D%3D%282.4x10%5E%7B6%7D%20i%20%2B%203.6x10%5E%7B6%7D%20j%29%20%5Cfrac%7B%5Bm%5D%7D%7B%5Bs%5D%7D%5C%5C%5C%5C)
In respect to the magnetic field; ![\overrightarrow{B}=(0.027 i - 0.15 j) [T]](https://tex.z-dn.net/?f=%5Coverrightarrow%7BB%7D%3D%280.027%20i%20-%200.15%20j%29%20%5BT%5D)
The magnetic force can be written as;
![\overrightarrow{F} = q(\overrightarrow{v} x \overrightarrow{B})\\ \\\\\overrightarrow{F}= q \left[\begin{array}{ccc}i&j&k\\2.4x10^{6}&3.6x10^{6}&0\\0.027&-0.15&0\end{array}\right]](https://tex.z-dn.net/?f=%5Coverrightarrow%7BF%7D%20%3D%20q%28%5Coverrightarrow%7Bv%7D%20x%20%5Coverrightarrow%7BB%7D%29%5C%5C%20%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%20q%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Di%26j%26k%5C%5C2.4x10%5E%7B6%7D%263.6x10%5E%7B6%7D%260%5C%5C0.027%26-0.15%260%5Cend%7Barray%7D%5Cright%5D)
Bear in mind ![q =-1.6021x10^{-19} [C]](https://tex.z-dn.net/?f=q%20%3D-1.6021x10%5E%7B-19%7D%20%5BC%5D%20)
thus,
![\overrightarrow{F}= q \left[\begin{array}{ccc}i&j&k\\2.4x10^{6}&3.6x10^{6}&0\\0.027&-0.15&0\end{array}\right]\\\\\\\overrightarrow{F}= q(2.4x10^{6}* (-0.15)- (0.027*3.6x10^{6}))\\\\\\\overrightarrow{F}= -1.6021x10^{-19} [C](-457200) [T]\frac{m}{s}\\\\\overrightarrow{F}=(7.3152x10^{-14}) k [\frac{N*m/s}{C*m/s}]\\\\|F|= \sqrt{ (7.3152x10^{-14})^{2}[N]^2 *k^{2}}\\\\F=7.3152x10^{-14} [N]](https://tex.z-dn.net/?f=%5Coverrightarrow%7BF%7D%3D%20q%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Di%26j%26k%5C%5C2.4x10%5E%7B6%7D%263.6x10%5E%7B6%7D%260%5C%5C0.027%26-0.15%260%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%20q%282.4x10%5E%7B6%7D%2A%20%28-0.15%29-%20%280.027%2A3.6x10%5E%7B6%7D%29%29%5C%5C%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%20-1.6021x10%5E%7B-19%7D%20%5BC%5D%28-457200%29%20%5BT%5D%5Cfrac%7Bm%7D%7Bs%7D%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%287.3152x10%5E%7B-14%7D%29%20k%20%5B%5Cfrac%7BN%2Am%2Fs%7D%7BC%2Am%2Fs%7D%5D%5C%5C%5C%5C%7CF%7C%3D%20%5Csqrt%7B%20%287.3152x10%5E%7B-14%7D%29%5E%7B2%7D%5BN%5D%5E2%20%2Ak%5E%7B2%7D%7D%5C%5C%5C%5CF%3D7.3152x10%5E%7B-14%7D%20%5BN%5D)
Note: The cross product is operated as a determinant. Likewise, the product of the unit vector k is squared and that is operated as dot product whose value is equal to one, i.e, 
(b) Considering the proton charge has the same magnitude as electron does, but the sign is positive, thus
![\overrightarrow{F}= q \left[\begin{array}{ccc}i&j&k\\2.4x10^{6}&3.6x10^{6}&0\\0.027&-0.15&0\end{array}\right]\\\\\\\overrightarrow{F}= q(2.4x10^{6}* (-0.15)- (0.027*3.6x10^{6}))\\\\\\\overrightarrow{F}= 1.6021x10^{-19} [C](-457200) [T]\frac{m}{s}\\\\\overrightarrow{F}=(-7.3152x10^{-14}) k [\frac{N*m/s}{C*m/s}]\\\\|F|= \sqrt{ (-7.3152x10^{-14})^{2}[N]^2 *k^{2}}\\\\F=-7.3152x10^{-14} [N]](https://tex.z-dn.net/?f=%5Coverrightarrow%7BF%7D%3D%20q%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Di%26j%26k%5C%5C2.4x10%5E%7B6%7D%263.6x10%5E%7B6%7D%260%5C%5C0.027%26-0.15%260%5Cend%7Barray%7D%5Cright%5D%5C%5C%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%20q%282.4x10%5E%7B6%7D%2A%20%28-0.15%29-%20%280.027%2A3.6x10%5E%7B6%7D%29%29%5C%5C%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%201.6021x10%5E%7B-19%7D%20%5BC%5D%28-457200%29%20%5BT%5D%5Cfrac%7Bm%7D%7Bs%7D%5C%5C%5C%5C%5Coverrightarrow%7BF%7D%3D%28-7.3152x10%5E%7B-14%7D%29%20k%20%5B%5Cfrac%7BN%2Am%2Fs%7D%7BC%2Am%2Fs%7D%5D%5C%5C%5C%5C%7CF%7C%3D%20%5Csqrt%7B%20%28-7.3152x10%5E%7B-14%7D%29%5E%7B2%7D%5BN%5D%5E2%20%2Ak%5E%7B2%7D%7D%5C%5C%5C%5CF%3D-7.3152x10%5E%7B-14%7D%20%5BN%5D)
Note: The cross product is operated as a determinant. Likewise, the product of the unit vector k is squared and that is operated as dot product whose value is equal to one, i.e,
Final remarks: The cross product was performed in R3 due to the geometrical conditions of the problem.
-- volume = (length)(width)(height)
-- Since the cube is a cube, its three dimensions are all the same number.
Volume = (2.5cm)(2.5cm)(2.5cm)
Volume = 15.625 cubic cm
-- density = (mass) / (volume)
Density = (1129.56g) / (15.625cm^3)
Density = 72.3 g/cm^3
(roughly 3.2 TIMES the density of the most dense naturally occurring substance on Earth)
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Answer: ANULAR ECLIPSE. Since the moon is too far, it will cover only a part of the sun, and only the external ring of the moon will be visible; this is called anular eclipse.
2) </span><span>anyone looking from the night side of earth can, in principle, see a -->
Answer: LUNAR ECLIPSE. If the moon is the right position, and the Earth's shadow covers partially or totally the moon, then a lunar eclipse occurs.
3) </span><span>during some lunar eclipses, the moon's appearance changes only slightly, because it passes only through the part of earth's shadow called the -->
Answer: PENUMBRA.
4) </span><span>a ... can occur only when the moon is new and has an angular size larger than the sun in the sky -->
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Direction!
Velocity is a vector quantity and speed is a scalar quantity. Vector quantities includes both magnitude and direction, while scalar quantities only have magnitude. :)
