Explanation:
Cell is a structural and fundamental unit mass of the body
Answer:
If you apply a force to separate 2 opposite poles, the potential energy of the system increases.
Answer:
191433.4 hours
Explanation:
We are given that In the average US household, the television is on 6.75 hours/day! How many hours will have passed after 77.7 years (the average lifeexpectancy of an American)?
1 year - 365 days
Given that the television is on 6.75 hours/day.
If 1 year = 365 days
Convert 77.7 years to days by multiplying it by 365
77.7 × 365 = 28360.5 days
So the number of hours will be:
28360.5 × 6.75 = 191433.375 hours
Therefore, 191433.4 hours will pass.
Non of the options is correct.
Complete Question
A 10 gauge copper wire carries a current of 20 A. Assuming one free electron per copper atom, calculate the drift velocity of the electrons. (The cross-sectional area of a 10-gauge wire is 5.261 mm2.)
mm/s
Answer:
The drift velocity is
Explanation:
From the question we are told that
The current on the copper is
The cross-sectional area is
The number of copper atom in the wire is mathematically evaluated
Where is the density of copper with a value
is the Avogadro's number with a value
Z is the molar mass of copper with a value
So
Given the 1 atom is equivalent to 1 free electron then the number of free electron is
The current through the wire is mathematically represented as
substituting values
=>
Answer:
6.57 m/s
Explanation:
First use Hook's Law to determine the F the compressed spring acts on the mass. Hook's Law F=kx; F=force, k=stiffnes of spring (or spring constant), x=displacement
F=kx; F=180(.3) = 54 N
Next from Newton's second law find the acceleration of the mass.
Newton's .2nd law F=ma; a=F/m ; a=54/.75 = 72m/s²
Now use the kinematic equation for velocity (or speed)
v₂²= v₀² + 2a(x₂-x₀); v₂=final velocity; v₀=initial velocity; a=acceleration; x₂=final displacement; x₀=initial displacment.
v₀=0, since the mass is at rest before we release it
a=72 m/s² (from above)
x₀=0 as the start position already compressed
x₂=0.3m (this puts the spring back to it's natural length)
v₂²= 0 + 2(72)(0.3) = 43.2 m²/s²
v₂= = 6.57 m/s