Answer:
a) 
b) 
Explanation:
From the question we are told that:
Wire Length 
Resistance 
Force 
Power 
a)
Generally the equation for Power is mathematically given by

Therefore



b)
Generally the equation for Magnetic Field is mathematically given by



Hi there!
Recall Newton's Law of Universal Gravitation:

Where:
Fg = Force of gravity (N)
G = Gravitational Constant
m1, m2 = masses of objects (kg)
r = distance between objects (m)
Plug in the given values stated in the problem:

Answer:
550000000N/m
Explanation:
Given that a copper wire has a radius of 2.9 mm. When forces of a certain equal magnitude but opposite directions are applied to the ends of the wire, the wire stretches by 5.0×10−3 of its original length.
Original length L = 0.005L
the strain = extension/ original length
the strain = 0.005L / L
the strain = 0.005
Young modulus = stress / strain
11 × 10^10 = stress / 0.005
Cross multiply
Stress = 11 × 10^10 × 0.005
Stress = 550 000000 N/m
Therefore, the tensile stress on the wire is 550000000 N/m.
Answer:

Explanation:
Given

r=2cm
Now angular velocity is given by 

Now linear velocity(v) is given =

Now tangential component of acceleration is given by

at t=0

radial component of acceleration is given by



at t=0

If you think more specifically about energy,such as thermal energy,the amount of that energy a substance has is determined by the movement of the molecules.hope this helps u