Here, as the charge is uniformly distributed in the sphere, we will consider s as an area of the sphere which is, s=4πr2 and r is radius of the gaussian surface shown in the figure above. From this, it can be seen that
Answer:
C) unbalanced
Explanation:
Equal forces acting in opposite directions are called balanced forces. Balanced forces acting on an object will not change the object's motion. When you add equal forces in opposite direction, the net force is zero.
Answer:
20N
Explanation:
The force (Hooke's Law) is proportional to the deformation. To extend the spring 4 times longer, you will need 4 times the force. In total, 20 N
Answer:
35.7 mA
Explanation:
The magnetic field inside a solenoid is given by:
(1)
where
is the vacuum permeability
I is the current
n is the number of turns per unit length
Since we have
N = 870 turns
L = 0.390 (length of the solenoid)
we can calculate n

And now we can re-arrange eq.(1) to find the current, I:

-1^10
centi=10 mm and mm=1/10=10^-1 cm