Answer:
P1 = 240 kPa.
Explanation:
Given the following data;
Initial volume = 0.3 m³
Final volume, V2 = 0.9 m³
Final pressure, P2 = 80 kPa
To find the initial pressure, we would use Boyle's law;
Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.
Mathematically, Boyles law is given by the formula;
Substituting into the formula, we have;




Therefore, the initial pressure of the gas is 240 kPa
Answer:
ionized particles from the sun.
* interactions in radiation belts.
* the friction of the planet in the solar wind
q = +9 10⁵ C
Explanation:
Due to being made up of matter, the planet Earth has a series of positive and negative charges, in general these charges should be balanced and the net charge of the planet should be zero, but there are several phenomena that introduce unbalanced charges, for example:
* ionized particles from the sun.
* interactions in radiation belts.
* the friction of the planet in the solar wind
This creates that the planet has a net electrical load
We can roughly calculate the charge of the planet
E = k q / r²
q = E r² / k
let's calculate
q = 200 (6.37 10⁶)²/9 10⁹
q = +9 10⁵ C
Answer:
5 W
Explanation:
The formula of the power is:
● P = W/t
W is the work and t is the time needed to do it(in seconds)
Let's calculate first the work that the force exerced:
W = Vector F . Vector d
D is the distance ( here 400 cm wich is 4 m)
Make a representation to see how are the vectors F and V.(picture below)
The vector F and d are colinear since Den is pushing the desk on the ground.
● W = 4 × 10 = 40 J
J is Joule
■■■■■■■■■■■■■■■■■■■■■■■■■■
● P = W / t
● P = 40/ 8
● P = 5 W
Answer:
Magnetic field, 
Explanation:
Given that,
Velocity of electron, 
It enters a region of space where perpendicular electric and a magnetic fields are present.
Magnitude of electric field, 
We need to find the magnetic field will allow the electron to go through the region without being deflected.
Magnetic force on the electron,
.......(1)
Electric force on the electron, F = q E........(2)
From equation (1) and (2) we get:



B = 0.0002 T
or

Hence, this is the required solution.
Answer:
v = -0.45 m/s
Explanation:
Assuming the canoe was initially at rest with momentum L = 0
and that the dog's velocity is in the positive direction
conservation of momentum
0 = 15(1.2) + 40v
v = -0.45 m/s