Answer:
number of electrons = 2.18*10^18 e
Explanation:
In order to calculate the number of electrons that move trough the second wire, you take into account one of the Kirchoff's laws. All the current that goes inside the junction, has to go out the junction.
Then, if you assume that the current of the wire 1 and 3 go inside the junction, then, all this current have to go out trough the second junction:
(1)
i1 = 0.40 A
i2 = 0.75 A
you solve the equation i3 from the equation (1):

Next, you take into account that 1A = 1C/s = 6.24*10^18
Then, you have:

The number of electrons that trough the wire 3 is 2.18*10^18 e/s
Answer:
60words/minute
Explanation:
If Sunitha can type 1800 words in half an hour, this can be expressed as;
1800 words = 30 minutes
To get her typing speed per minute, we will use the formula
Speed = Number of words/Time used
Typing speed = 1800/30
Typing speed = 60words/minute
Hence her typing speed in words per minute is 60words/minute
Answer:
7350 J
Explanation:
The gravitational potential energy of the rock sitting on the edge of the cliff is given by:

where
m is the mass of the rock
g is the gravitational acceleration
h is the height of the cliff
In this problem, we have
m = 50 kg
g = 9.8 m/s^2
h = 15 m
Substituting numbers into the formula, we find:

In this question, you are given the energy( 500,000btus) and the temperature difference( 100F-20F= 80F). You are asked to find the volume of water.
1 BTU mean 1 degree of F increased for 1 pound mass. First, we can calculate the mass of the water in lb unit. The calculation would be:
mass= energy/temperature increase = 500,000/80= 6250lb.
Then we need to convert the weight into gallons. The calculation would be:
6250lb x kg/2.204lb x 1kg/m3 x 264.172 gallons/m3= 3638969.3 gallons
Answer:
We know that the speed of sound is 343 m/s in air
we are also given the distance of the boat from the shore
From the provided data, we can easily find the time taken by the sound to reach the shore using the second equation of motion
s = ut + 1/2 at²
since the acceleration of sound is 0:
s = ut + 1/2 (0)t²
s = ut <em>(here, u is the speed of sound , s is the distance travelled and t is the time taken)</em>
Replacing the variables in the equation with the values we know
1200 = 343 * t
t = 1200 / 343
t = 3.5 seconds (approx)
Therefore, the sound of the gun will be heard at the shore, 3.5 seconds after being fired