Answer:
A charge of -5.02 nC is uniformly distributed on a thin square sheet of nonconducting material of edge length 21.8 cm. "What is the surface charge density of the sheet"?
Explanation:
Surface charge density is a measure of how much electric charge is accumulated over a surface. It can be calculated as the charge per unit area.
We will convert all parameters in SI units.
Charge = Q = -5.02nC
Q = -5.02×
C
As it is clear from question that Sheet is a square (All sides will be of equal length)
Area = A = (21.8×
m) (21.8×
m) = 4.75×
m²
A = 4.75×
m²
Surface charge density = Q/A
Surface charge density = (-5.02×
C)/(4.75×
m²)
Surface charge density = -1.057×
C
Opposite to the direction of the velocity which led it to its current position.
Explanation:
The direction of momentum when a vertically oscillating block comes to the rest momentarily will be opposite to the direction of the velocity that it has just followed to reach reach its current position.
The direction of change in momentum at the bottom will be upwards and at the top will be downwards.
The change in momentum is mathematically defined as:

where:
mass of the block
final velocity of the block
initial velocity of the block
When the block comes to rest it is due to the result of continuously decreasing velocity.
Answer:
a. Weight of Object in Water = 20 N
b. Up thrust = 20 N
c. Weight of Water Displaced = 20 N
Explanation:
a.
The weight of the object remains same in the water as well. Because, the same force of gravity is acting there as well. Hence,
<u>Weight of Object in Water = 20 N</u>
<u></u>
b.
Since, the object floats on the water. Therefore, according to Archimedes' principle the up thrust force acting on the object must be equal to the weight of object:
Up thrust = Weight of object
<u>Up thrust = 20 N</u>
<u></u>
c.
From Archimedes' Principle, we know that the up thrust or the Buoyant force is equal to the weight of the water displaced by the object. therefore:
Weight of Water Displaced = Up thrust
<u>Weight of Water Displaced = 20 N</u>
Answer:
The speed of the bob when it passes the lowest point 
Explanation:
Given data

When a pendulum swinging back & forth then at highest point the velocity is zero and lowest point velocity is maximum.
Velocity at lowest point is given by



Therefore the speed of the bob when it passes the lowest point 