A chain 72 meters long whose mass is 29 kilograms is hanging over the edge of a tall building and does not touch the ground. How
1 answer:
Answer:
Work done required is 3567.2 J
Explanation:
Given :
Length of chain, l = 72 m
Mass of chain, M = 29 kg
Linear mass density of chain, μ = =
= 0.40 kg/m
Let x be the length of the chain which lift to the top of the building.
Work done required to lift the chain is equal to the potential energy of the chain.
W = ∫μg (72 - x ) dx
Here g is acceleration due to gravity.
The limit of integration is from 0 to 14.
W = μg ( 72x - x²/2)
Substitute 0.40 kg/m for μ, 9.8 m/s² for g and 14 m for x in the above equation.
W =
W = 3567.2 J
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Answer:
The number of electrons that must be moved from one electrode to the other to accomplish this is 1.4 X 10⁹ electrons.
Explanation:
<u>Step 1:</u> calculate the charge on each electrode
Given;
Electric field strength = 2.0 X 10⁶ N/C
The distance between the electrode = 1mm = 1 X 10⁻³ m
Electric field strength (E) = Force (F)/Charge (q)
where;
E is the electric field strength = 2.0 X 10⁶ N/C
K is coulomb's constant = 8.99 X 10⁹ Nm²/C²
r is the distance between the electrodes = 1 X 10⁻³ m
q is the charge in each electrode = ?
= 0.2225 X 10⁻⁹ C
The charge on each electrode is 0.2225 X 10⁻⁹ C
<u>Step 2:</u> calculate the number of electrons to be moved from one electrode to the other.
1 electron contains 1.602 X 10⁻¹⁹ C
So, 0.2225 X 10⁻⁹ C will contain how many electrons ?
= (0.2225 X 10⁻⁹)/(1.602 X 10⁻¹⁹)
= 1.4 X 10⁹ electrons
Therefore, the number of electrons that must be moved from one electrode to the other to accomplish this is 1.4 X 10⁹ electrons.