Answer:
Explanation:
A point charge of +2q centered in a conductive spherical shell of inner diameter a and outer diameter b will induce - 2q charge on the inner surface and +2q charge on the outer surface of the shell. Since 8q charge has been added to the shell , this charge will reside on the outer surface of the shell. so total charge on the outer surface will be 10q. At a point less than a , the electric field will be due to +2q charge situated at the centre . The electric field will be as follows
E = k .2q / r² for r < a
= 8kq/ a²
electric field at a point r = a>b
total charge lying inside is +2q - 2q = 0 . So in the thickness of the shell , electric field will be zero as total charge inside is nil.
For a point at r > b total charge inside is 2q-2q+10q = 10q , so electric field at r which is lying outside the shell .
E = k 10 q / r² for r > b
Explanation:
The relative velocity is the velocity of the athlete relative to the ground plus the velocity of the javelin relative to the athlete.
v = 4.2 m/s + 10.3 m/s
v = 14.5 m/s
Clues or evidence
Im pretty sure its evidence though
Answer:D
Explanation:
When the character falls off from cliff he moves away from the observer as he falls down and hence the frequency heard by observer lowers as he falls.
Therefore the pitch of the sound is lower than the original sound and decreasing as he falls
Option D is the correct choice
Answer:
Explanation:
A closed system is a system where exists energy interactions with surroundings, but not mass interactions. If we neglect any energy interactions from boundary work, heat, electricity, magnetism and nuclear phenomena and assume that process occurs at steady state and all effects from non-conservative forces can be neglected, then the equation of energy conservation is reduce to this form:
(1)
Where:
- Change in kinetic energy of the system, measured in joules.
- Change in gravitational potential energy of the system, measured in joules.
If we know that 
and 
, then we get the following equation:
(2)
Where 
and 
stands for initial and final states of each energy component.
Hence, the right answer is
