Answer:
The total charge Q of the sphere is
.
Explanation:
Given that,
Radius = 5 cm
Charge density 
We need to calculate the total charge Q of the sphere
Using formula of charge

Where,
= charge density
V = volume
Put the value into the formula

Put the value into the formula


Hence, The total charge Q of the sphere is
.
Answer:
Work cause a change in kinetic energy
Answer:
Speed of the boat, v = 4.31 m/s
Explanation:
Given that,
Height of the bridge, h = 32 m
The model boat is 11 m from the point of impact when the key was released, d = 11 m
Firstly, we will find the time needed for the boat to get in this position using second equation of motion as :

Here, u = 0 and a = g


t = 2.55 seconds
Let v is the speed of the boat. It can be calculated as :


v = 4.31 m/s
So, the speed of the boat is 4.31 m/s. Hence, this is the required solution.
All ions are atoms with a charge