Answer:
284.4233 N/m
Explanation:
k = Spring constant
x = Compression of spring = 14.5 cm
U = Potential energy = 2.99 J
The potential energy of a spring is given by

Rearranging to get the value of k

The spring constant is 284.4233 N/m
Answer:
The potential difference is 121.069 V
Solution:
As per the question:
Diameter of the cylinder, d = 9.0 cm = 0.09 m
Length of the cylinder, l = 40 cm = 1.4 m
Average Resistivity, 
Current, I = 100 mA = 0.1 A
Now,
To calculate the potential difference between the hands:
Cross- sectional Area of the Cylinder, A = 
Resistivity is given by:



Now, using Ohm's Law:
V = IR

Answer:
F=5449 N
Explanation:
Work done is a product of force and displacement ie
Work done, W, = Force*Displacement
Power, P, is Work done/Time
where P is power, W is work done, F is force, S is displacement and t is time
In this case, F is the frictional force. Converting the power from hp to W, we multiply by 746 hence P=746*168=125328 W
Since displacement/time is velocity, then
P=FV where V is velocity in m/s
Making F the subject


F=5449 N
<span>Methods of extraction include: extract by electrolysis, extract by reaction with carbon or carbon monoxide, and extracted by various chemical reactions.</span>