Answer: 1.3 *10^6 Ω*m
Explanation: In order to explain this problem we have to use the following expression for the resistence:
R=L/(σ*A) where L and A are the length and teh area for the wire, respectively. σ is the conductivity of teh Nichrome.
Then, from mteh OHM law we have V=R*I so R=V/I=2/3.2=0.625 Ω
Finally we have:
σ=L/(R*A)=1.3/(0.625*1.6*10^-6)=1.3*10^6 Ω*m
Answer:
0.009 N, repulsive
Explanation:
The electrostatic force between two electric charges is given by:
where
k is the Coulomb's constant
q1 and q2 are the two charges
r is the separation between the two charges
In this problem, we have
are the two charges
r = 4.5 m is their separation
Substituting into the equation, we find
Moreover, the force is repulsive. In fact, the following rules apply:
- When two charges have same sign, they repel each other
- When two charges have opposite signs, they attract each other
Answer:
692.31 N
Explanation:
Applying,
F = ma............... Equation 1
Where F = Average force required to stop the player, m = mass of the player, a = acceleration of the player
But,
a = (v-u)/t............ Equation 2
Where v = final velocity, u = initial velocity, t = time.
Substitute equation 2 into equation 1
F = m(v-u)/t............ Equation 3
From the question,
Given: m = 75 kg, u = 6.0 m/s, v = 0 m/s (to stop), t = 0.65 s
Substitute these values into equation 3
F = 75(0-6)/0.65
F = -692.31 N
Hence the average force required to stop the player is 692.31 N
Answer:
b.
Explanation:
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