Answer:


Explanation:
k = Coulomb constant = 
Q = Charge
r = Distance = 8 cm
R = Radius = 4 cm
Electric field is given by

Volume charge density is given by

The volume charge density for the sphere is 

The magnitude of the electric field is 
Answer:
The mass of Uranium present in a 1.2mg sample is 
Explanation:
The ration between Uranium mass and total sample mass is:
For a sample of mass 1.2 mg, the amount of uranium is:

Answer:
a) false
b) True
c) True
d) False
e) False
Explanation:
a) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
b) True
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
c) True
d) False
For a diverging lens, the focal length is negative while it is positive for a converging lens
e) False
Image distances for virtual images are always negative and it also forms on the the same side of the lens as the object and is enlarged
Answer:
The second one, the higher the hertz the higher the frequency we hear
Explanation:
A = Delta v/Delta t
Delta v = 25 - 0 = 25
Delta t = 30
25/30 = 5/6 = 1.66 repeating