Answer:
The excess charge on earth's surface was calculated to be 4.56 × 10⁵ C
Explanation:
Using the formula for an electric field;
E = kQ/r²
k = 1/(4πε₀) = 8.99 × 10⁹ Nm²/C²
E = 100N/C
r = radius of the earth = 6400 km = 6400000m
Q = Er²/k = 100 × (6400000)²/(8.99 × 10⁹)
Q = 455617.4 C = 4.56 × 10⁵ C
Hope this helps!!!
The watt is a rate, similar to something like speed (miles per hour) and other time-interval related measurements.
Specifically, watt means Joules per Second. We are given that the electrical engine has 400 watts, meaning it can make 400 joules per second. If we need 300 kJ, or 3000 Joules, then we can write an equation to solve the time it would take to reach this amount of joules:
w * t = E
w: Watts
t: Time
E: Energy required
(Watts times time is equal to the energy required)
<u>Input our values:</u>
400 * t = 3000
(We need to write 3000 joules instead of 300 kilojoules, since Watts is in joules per second. It's important to make sure your units are consistent in your equations)
<u>Divide both sides by 400 to isolate t:</u>
<u />
= 
t = 7.5 (s)
<u>It will take 7.5 seconds for the 400 W engine to produce 300 kJ of work.</u>
<u></u>
If you have any questions on how I got to the answer, just ask!
- breezyツ
Answer:
16.8 lb is the force on the brake pad of one wheel.
Explanation:
Force applied on the piston = 
Area of the piston = 
Force applied on the brakes = 
Area of the brakes = 
Applying Pascal's law: 'For an incompressible fluid pressure at one surface is equal to the pressure at other surface'.


16.8 lb is the force on the brake pad of one wheel.
Answer:

Explanation:
The electric flux is defined as the multiple of electric field and the area that the electric field passes through, such that

When calculating the electric flux, the angle between the directions of electric field and the area becomes important, especially if the angle is changing with time.
The above formula can be rewritten as follows

where θ is the angle between the electric field and the area of the loop. Note that, the direction of the area of the loop is perpendicular to the plane of the loop.
If the loop is rotating with constant angular velocity ω, then the angle can be written as follows

At t = 0, cos(0) = 1 and the electric flux through the loop is at its maximum value.
Therefore the electric flux can be written as a function of time
