The answer is either answer B or answer C! Hope that helps
Answer:
Explanation:
Given
Electric Field 
velocity 
mass of electron 
Force on a charge Particle moving in Magnetic Field
![F=e\left [ \vec{E}+\left ( \vec{v}\times \vec{B}\right )\right ]](https://tex.z-dn.net/?f=F%3De%5Cleft%20%5B%20%5Cvec%7BE%7D%2B%5Cleft%20%28%20%5Cvec%7Bv%7D%5Ctimes%20%5Cvec%7BB%7D%5Cright%20%29%5Cright%20%5D)
![a=\frac{e\left [ \vec{E}+\left ( \vec{v}\times \vec{B}\right )\right ]}{m}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7Be%5Cleft%20%5B%20%5Cvec%7BE%7D%2B%5Cleft%20%28%20%5Cvec%7Bv%7D%5Ctimes%20%5Cvec%7BB%7D%5Cright%20%29%5Cright%20%5D%7D%7Bm%7D)
![a=\frac{1.6\times 10^{-19}\left [ 2\hat{i}+5.4\hat{j}+\left ( 8\hat{i}\times 0.4\hat{k}\right )\right ]}{9.1\times 10^{-31}}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7B1.6%5Ctimes%2010%5E%7B-19%7D%5Cleft%20%5B%202%5Chat%7Bi%7D%2B5.4%5Chat%7Bj%7D%2B%5Cleft%20%28%208%5Chat%7Bi%7D%5Ctimes%200.4%5Chat%7Bk%7D%5Cright%20%29%5Cright%20%5D%7D%7B9.1%5Ctimes%2010%5E%7B-31%7D%7D)
Answer:
15.4 kg.
Explanation:
From the law of conservation of momentum,
Total momentum before collision = Total momentum after collision
mu+m'u' = V(m+m').................... Equation 1
Where m = mass of the first sphere, m' = mass of the second sphere, u = initial velocity of the first sphere, u' = initial velocity of the second sphere, V = common velocity of both sphere.
Given: m = 7.7 kg, u' = 0 m/s (at rest)
Let: u = x m/s, and V = 1/3x m/s
Substitute into equation 1
7.7(x)+m'(0) = 1/3x(7.7+m')
7.7x = 1/3x(7.7+m')
7.7 = 1/3(7.7+m')
23.1 = 7.7+m'
m' = 23.1-7.7
m' = 15.4 kg.
Hence the mass of the second sphere = 15.4 kg
