12 V is the f.e.m.
of the battery. The potential difference that is applied to the motor is actually the fem minus the voltage drop on the internal resistance r:
this is equal to the voltage drop on the resistance of the motor R:
so we can write:
and using
and
we can find the current I:
Answer:
No, because pressure is determined by force and the area over which that force acts.
Explanation:
Answer:drift velocity is 1.7*10^-4m/s and number of charge is 2.7*10^-24
Explanation:
Answer: A
Explanation:
Molecules speed up as heat is added
For example when water is heated as the water gets hotter the molecules speed up causing the water to boil and change phases into a gas (this is called evaporation)
In an ice cube the water molecules are frozen (barely moving compressed tight together) as the ice cube heats up the molecules start speeding up and moving further apart as the ice cube turns into liquid form. So as heat is added molecules speed up, move faster and spread further apart
Answer:
a). Determine the magnitude of the gravitational force exerted on each by the earth.
Rock: 
Pebble: 
(b)Calculate the magnitude of the acceleration of each object when released.
Rock: 
Pebble:
Explanation:
The universal law of gravitation is defined as:
(1)
Where G is the gravitational constant, m1 and m2 are the masses of the two objects and r is the distance between them.
<em>Case for the rock </em>
<em>:</em>
m1 will be equal to the mass of the Earth 
and since the rock and the pebble are held near the surface of the Earth, then, r will be equal to the radius of the Earth 
.
Newton's second law can be used to know the acceleration.
(2)
<em>Case for the pebble </em>
<em>:</em>
