Answer:
Variance is
Solution:
As per the question:
Average value of the steam, = 25000 pounds per hour,
To calculate the variance, of the steam:
where
= standard deviation
at 0.8 is 1.285 from Z-table
Thus
Variance,
Answer:
The force (thrust) is equal to the exit mass flow rate times the exit velocity minus the free stream mass flow rate times the free stream velocity.
Answer:
A) 0 for r < R B) Q/4πε₀r² for r > R
Explanation:
Here is the complete question
Part A Find the electric field inside a hollow plastic ball of radius R that has charge Q uniformly distributed on its outer surface. Give your answer as a multiple of Q/ε0.
Part B Find the electric field outside this ball. Give your answer as a multiple of Q/ε0. Express your answer in terms of some or all of the variables R, r and the constant π.
Solution
Using Gauss' law ∫E.dA = q/ε₀. Where E is the electric field, dA is the area vector and q is the charge enclosed.
A For r < R The direction of the electric field is directed radially inward and r is outward and the angle between them is 180°. So E.dA = EdAcos180 = -EdA
∫-EdA = q/ε₀
-E∫dA = q/ε₀
-E4πr² = q/ε₀ (∫dA = 4πr² since it is a sphere)
E = -q/4πr²ε₀
But for r < R q = 0. So,
E = -q/4πr²ε₀ = -0/4πr²ε₀ = 0
B For r > R The direction of the electric field is directed radially outward and r is outward and the angle between them is 0°. So E.dA = EdAcos0 = EdA
∫EdA = q/ε₀ where Q is the charge on the hollow plastic ball
E∫dA = q/ε₀
E4πr² = q/ε₀ (∫dA = 4πr² since it is a sphere)
E = q/4πr²ε₀
But for r > R q = Q. So,
E = Q/4πr²ε₀ = Q/4πε₀r²
10 m/s² to the left.
<h3>
Further explanation</h3>
<u>Given: </u>
- The mass of a stuffed bear = 200 grams = 0.2 kg.
- The mass of a boy = 25 kg.
- The mass of a girl = 20 kg.
- A boy pulls to the right with a 15 N force.
- A girl pulls to the left with a 17 N force.
<u>Question:</u>
What the acceleration of the bear is?
This is the case for implementing Newton's second law, i.e., 'the resultant force is proportional to the acceleration'. If we also use SI units then 'the resultant force is equal to the product of the mass and the acceleration'.
- The net force, i.e., is the resultant of all forces acting on an object, measured in newtons (kgm/s²).
- The mass measured is kilograms.
- The acceleration measured in m/s².
Let's calculate the net force.
Referring to the horizontal axis marked a positive to the right, then
A negative sign indicates that the bear is moving to the left.
We continue to calculate the bear's acceleration. Remember, the mass that is applied is the mass of the bear that is accelerating.
Thus, the magnitude and direction of the acceleration is
<h3>Learn more</h3>
- Express the answer to three significant figures brainly.com/question/3959122
- A correct representation of 0.000025 in scientific notation brainly.com/question/2261308
- The theoretical density of platinum which has the FCC crystal structure brainly.com/question/5048216
Keywords: two children, a 200 g stuffed bear, the 25 kg boy pulls to the right, a 15 n force, the 20 kg girl, left, a 17 n, what the acceleration, newton's second law, the magnitude and direction