Explanation:
It is given that,
Potential difference between the ends of a rod, V = 1.1 V
Length of the rod, l = 10 cm = 0.1 m
Area of cross section of the rod, 
The resistivity of graphite, 
(a) Let R is the resistance of the rod. It is given by :



So, the resistance of the rod is 0.833 ohms.
(b) Let I is the current flowing in the wire. It can be calculated using the Ohm's law as :


I = 1.32 A
(c) Let E is the electric field inside the rod. The electric field in terms of potential difference is given by :


E = 11 V/m
Hence, this is the required solution.
Answer:
m1 = 20g (= 0.02 kg)
Mass of pistol, m2 = 2 kg
Initial velocity of the bullet (u1) and pistol (u2) = 0
Final velocity of the bullet, v1 = +150m s-1
Let v be the recoil velocity of the pistol.
Total momentum of the pistol and bullet after it is fired is
= (0.02 kg x 150 m s-1) + (2 kg x v m s-1)
= (3 + 2v) kg m s-1
Total momentum after the fire = Total momentum before the fire
3 + 2v = 0
→v = -1.5 m/s
Answer: Option (c) is the correct answer.
Explanation:
Atomic number of hydrogen is 1 and one dot in its lewis structure displays only one electron. So, in order to complete its octet it needs one more electron.
Atomic number of carbon is 6 and its electronic distribution is 2, 4. Carbon needs 4 more electrons in order to complete its octet.
Atomic number of oxygen is 8 and its electronic distribution is 2, 6. In order to complete octet, oxygen needs 2 more electrons.
Atomic number of fluorine is 9 and its electronic distribution is 2, 7. In order to complete octet, fluorine needs 1 more electron.
Hence, we can conclude that out of the given options, lewis dot structure of oxygen atom needs 2 more electrons in its outermost shell.
Work = force x distance
So we are looking for something related to displacement.
The work done must also be done in the same direction, parallel to the displacement, and therefore in the same direction of the motion as well.
So:
In order to do work, the force vector must be in the same direction as the displacement vector and the motion.
(a) The force exerted by the electric field on the plastic sphere is equal to

where

is the charge of the sphere and E is the strength of the electric field. This force should balance the weight of the sphere:

where m is the mass of the sphere and g is the gravitational acceleration.
Since the two forces must be equal, we have:

and so we find the intensity of the electric field

(b) Now let's find the direction of the field. The electric force must balance the weight of the sphere, which is directed downward, so the electric force should be directed upward. Since the charge is negative, the force is opposite to the electric field direction, and so the direction of the electric field is downward.