Answer:
(a) Current is 2831.93 A
(b) 
(c) 
Explanation:
Length of wire l = 3.22 m
Diameter of wire d = 7.32 mm = 0.00732 m
Cross sectional area of wire
Resistance 
Potential difference V = 33.7 volt
(A) current is equal to
(B) Current density is equal to
(c) Resistance is equal to
Answer:
2677.3 N
Explanation:
v₀ = initial speed of the hand = 4.75 m/s
v = final speed of the hand = 0 m/s
m = Total mass of hand and forearm = 1.55 kg
t = time interval for hand to come to rest = 2.75 ms = 0.00275 s
F = Force applied on the leg
Using Impulse-change in momentum equation
F t = m (v - v₀)
F (0.00275) = (1.55) (0 - 4.75)
F = - 2677.3 N
magnitude of force = 2677.3 N
The elastic potential energy (Ep) is given by
Data:
Ep = ? (Joule)
k = 20 N/m
x (displacement) = 0.20 m
Solving:
Newton's law of conservation states that energy of an isolated system remains a constant. It can neither be created nor destroyed but can be transformed from one form to the other.
Implying the above law of conservation of energy in the case of pendulum we can conclude that at the bottom of the swing the entire potential energy gets converted to kinetic energy. Also the potential energy is zero at this point.
Mathematically also potential energy is represented as
Potential energy= mgh
Where m is the mass of the pendulum.
g is the acceleration due to gravity
h is the height from the bottom z the ground.
At the bottom of the swing,the height is zero, hence the potential energy is also zero.
The kinetic energy is represented mathematically as
Kinetic energy= 1/2 mv^2
Where m is the mass of the pendulum
v is the velocity of the pendulum
At the bottom the pendulum has the maximum velocity. Hence the kinetic energy is maximum at the bottom.
Energy can neither be created e destroyed. It can only be transferred from one form to another. Implying this law and the above explainations we conclude that at the bottom of the pendulum,the potential energy=0 and the kinetic energy=294J as the entire potential energy is converted to kinetic energy at the bottom.
