1) Current in the wire: 0.0875 A
The current in the wire is given by:

where
Q is the charge passing a given point in the conductor
t is the time elapsed
In this problem, we have
Q = 420 C is the total charge passing through a given point in a time of
t = 80 min = 4800 s
So, the current is

2) Drift velocity of the electrons: 
The drift velocity of the electrons in the wire is given by:

where
I = 0.0875 A is the current
is the number of free electrons per cubic meter
A is the cross-sectional area
is the charge of one electron
The radius of the wire is

So the cross-sectional area is

So, the drift velocity is

Answer:
a) factor 
b) factor 
c) factor 
d) factor 
Explanation:
Time period of oscillating spring-mass system is given as:


where:
frequency of oscillation
mass of the object attached to the spring
stiffness constant of the spring
a) <u>On doubling the mass:</u>
- New mass,

<u>Then the new time period:</u>




where the factor
as asked in the question.
b) On quadrupling the stiffness constant while other factors are constant:
New stiffness constant, 
<u>Then the new time period:</u>

where the factor
as asked in the question.
c) On quadrupling the stiffness constant as well as mass:
New stiffness constant, 
New mas, 
<u>Then the new time period:</u>

where factor
as asked in the question.
d) On quadrupling the amplitude there will be no effect on the time period because T is independent of amplitude as we can observe in the equation.
so, factor 
Answer:
1) 50 seconds 2) 100°C
Explanation:
(Follows formula of Power=Energy/Time)
1) 500W x X = 2000J/kg°C x .25kg x 50°C
X = 50 seconds.
2) 2000W x 300s = 1000J/kg°C x 2kg x X
X = 300
Initial temperature => 400°C-300°C = 100°C
Answer:
μ = 0.535
Explanation:
On a level floor, normal force = weight.
N = W
Friction force = normal force × coefficient of friction.
F = Nμ
Substitute:
F = Wμ
83 = 155μ
μ = 0.535
Round as needed.