The acceleration due to gravity serves as the centripetal acceleration of the objects that orbits the Earth. The centripetal acceleration due to gravity is calculated through the equation,
a = v²/r
where v is the speed and r is the radius. Substituting the known values to the equation,
9.8 m/s² = (420 m/s)² / r
The value of r from the equation is 18000 m or equal to 18 km.
<em>Answer: 18 km</em>
If a point has 40 J of energy and the electric potential is 8 V, the charge must be: A. 5 C
<u>Given the following the details;</u>
- Electric potential = 8 Volts
To find the quantity of charge;
Mathematically, the quantity of charge with respect to electric potential is given by the formula;

Substituting the values into the formula, we have;

<em>Quantity of charge = 5 Coulombs</em>
Therefore, the quantity of charge must be <em>5 Coulombs.</em>
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Since work is the change in kinetic energy, the efficiency of a machine can be stated as the percentage of the output work divided by the input work minus the work lost from to friction and heat. Multiply Eff by 100% to get the efficiency percentage.
The third one sliding friction
Explanation:
Answer:
Explanation:
There will not be any internal reflection . it will be only refraction
critical angle = θ
Sinθ = 1 / μg
μg = 1.43 / 1.33 =
Sinθ = 1.33 / 1.43
= .93
θ = 68.44
angle of incidence i = 68.44 / 2
= 34.22
Sin i / Sin r = μw = 1.33 / 1.43
= .93
sin 34.22 / sinθ₁ = .93 , θ₁ is angle of refraction.
sinθ₁ = sin 34.22 / .93
= .5623 / .93
= .6047
θ₁ = 37 degree Ans