As we know that spring force is given as

here we know that
F = 4 N
x = 2 cm = 0.02 m
now from the above equation we will have


so the elastic constant of the spring will be 200 N/m
Work done is 0.442J
<u>Explanation:</u>
Given:
Spring constant, k = 33 N/m
Distance, x₁ = 0.15m
Additional distance, x₂ = 0.072 m
Total distance = 0.15 + 0.072 m
= 0.222 m
Work done, W = ?
We can calculate work done by the formula

On substituting the value we get:
![W = \frac{1}{2}k [(x_2)^2 - (x_1)^2]\\ \\W = \frac{1}{2} X 33[(0.222)^2 - (0.15)^2]\\ \\W = \frac{1}{2}X 33 [ 0.0493 - 0.0225]\\ \\W = 0.442 J](https://tex.z-dn.net/?f=W%20%3D%20%5Cfrac%7B1%7D%7B2%7Dk%20%5B%28x_2%29%5E2%20%20-%20%28x_1%29%5E2%5D%5C%5C%20%5C%5CW%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20X%2033%5B%280.222%29%5E2%20-%20%280.15%29%5E2%5D%5C%5C%20%5C%5CW%20%3D%20%5Cfrac%7B1%7D%7B2%7DX%2033%20%5B%200.0493%20-%200.0225%5D%5C%5C%20%5C%5CW%20%3D%200.442%20J)
Therefore, work done is 0.442J
Answers:
1) flow of traffic = 
2) average speed = 
3)density of traffic = 
Explanation:
1) to find flow of traffic
we use the relation

where q is the traffic flow and h is average time headway.

insert the value

2) to find average traffic speed
use the relation

where u is average speed S is average spacing and h average time

so inserting the values

3) density of traffic

where K is density of traffic q is flow of traffic and u is average speed
inserting values from above solved parts

Answer: Magnitude of the electric field at a point which is 2.0 mm from the symmetry axis is 18.08 N/C.
Explanation:
Given: Density = 80
(1 n =
m) = 
= 1.0 mm (1 mm = 0.001 m) = 0.001 m
= 3.0 mm = 0.003 m
r = 2.0 mm = 0.002 m (from the symmetry axis)
The charge per unit length of the cylinder is calculated as follows.

Substitute the values into above formula as follows.
![\lambda = \rho \pi (r^{2}_{2} - r^{2}_{1})\\= 80 \times 10^{-9} \times 3.14 \times [(0.003)^{2} - (0.001)^{2}]\\= 2.01 \times 10^{-12} C/m](https://tex.z-dn.net/?f=%5Clambda%20%3D%20%5Crho%20%5Cpi%20%28r%5E%7B2%7D_%7B2%7D%20-%20r%5E%7B2%7D_%7B1%7D%29%5C%5C%3D%2080%20%5Ctimes%2010%5E%7B-9%7D%20%5Ctimes%203.14%20%5Ctimes%20%5B%280.003%29%5E%7B2%7D%20-%20%280.001%29%5E%7B2%7D%5D%5C%5C%3D%202.01%20%5Ctimes%2010%5E%7B-12%7D%20C%2Fm)
Therefore, electric field at r = 0.002 m from the symmetry axis is calculated as follows.

Substitute the values into above formula as follows.

Thus, we can conclude that magnitude of the electric field at a point which is 2.0 mm from the symmetry axis is 18.08 N/C.