Given :
Mass of water, m = 2 grams.
The temperature of water drops from 31 °C to 29 °C .
The specific heat of water is 4.184 J/(g • °C).
To Find :
Amount of heat lost in this process.
Solution :
We know, heat lost is given by :

Therefore, amount of heat lost in this process is 16.736 J.
Answer:
Explanation:
The application of Gauss's law is used in the derivation as shown with detailed step by step in the attached file.
The potential difference on this spherical capacitor is ΔV = Va - Vb = kQ/a - kQ/b = kQ(1/a - 1/b)
Answer:
The new potential energy decreases by the factor of 2 to the old potential energy.
Explanation:
Capacitance of a parallel plate capacitor is given by the relation :
C = (ε₀A)/d
Here ε₀ is vacuum permittivity, A is area of the capacitor plate and d is the distance between them.
Potential energy of the capacitor, U = 
Here V is the potential difference between the plates.
According to the problem, the distance between the plates get double but area remains same. So,
d₁ = 2d
Here d₁ is new distance between the plates.
Hence, new capacitance is :
C₁ = (ε₀A)/d₁ = (ε₀A)/2d = C/2
The capacitor have same potential difference that is V. Hence, the new potential energy is :
U₁ =
= 
U₁ = U/2

Answer:
<em>The cantaloupe has a speed of 117.6 m/s</em>
Explanation:
<u>Free Fall Motion</u>
It occurs when an object falls under the sole influence of gravity. Any object that is being acted upon solely by the force of gravity is said to be in a state of free fall. Free-falling objects do not face air resistance.
If an object is dropped from rest in a free-falling motion, it falls with a constant acceleration called the acceleration of gravity, which value is
.
The final velocity of a free-falling object after a time t is given by:
vf=g.t
The cantaloupe has been dropped from rest. We are required to find the speed after t=12 seconds.
Calculate the final speed:
vf=9.8 * 12 = 117.6 m/s
The cantaloupe has a speed of 117.6 m/s