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:
t = 2 s
Explanation:
As we know that fish is pulled upwards with uniform maximum acceleration
then we will have

here we know that maximum possible acceleration of so that string will not break is given as

now we have


now for such acceleration we can use kinematics


t = 2 s
Answer:
Explanation:
Calculate the volume of the lead

Now calculate the bouyant force acting on the lead


This force will act in upward direction
Gravitational force on the lead due to its mass will act in downward direction
Hence the difference of this two force

If V is the volume submerged in the water then bouyant force on the bobber is

Equate bouyant force with the tension and gravitational force

Now Total volume of bobble is

=
When boat is sunk into the liquid the net buoyancy on the boat is counterbalanced by weight of the boat
So here weight of the boat = Buoyancy force
let say boat is sunk by distance "h"
now we can say


now by above force balance equation we can write




so boat will sunk by total 5 mm distance
Answer:
Explanation:
If a particle move with time and expressed according to the formula:
f(t) = 0.01t⁴ − 0.03t³
a) Velocity is the change in motion of the particle with respect to time and it is expressed as;


Hence the velocity of the particle at time t is 
b) To calculate the velocity after 1 second, we will substitute t = 1 into the function v(t) in (a) as shown:

Hence the velocity after 1second is -0.05
c) The particle is at rest when when the time is zero.
Initially, the body is not moving and the time during this time is 0. Hence the particle is at rest when t = 0second