Answer:
The potential difference between the places is 0.3 V.
∴ 1st option i.e. 0.3V is the correct option.
Explanation:
Given
Work done W = 3J
Amount of Charge q = 10C
To determine
We need to determine the potential difference V between the places.
The potential difference between the two points can be determined using the formula
Potential Difference (V) = Work Done (W) / Amount of Charge (q)
or

substituting W = 3 and q = 10 in the formula

V
Therefore, the potential difference between the places is 0.3 V.
∴ 1st option i.e. 0.3V is the correct option.
Answer:
b.it depends on the distance it falls
Answer:
A. The waves in the water travel faster and at a higher frequency than they travel on land.
Explanation:
The main reason why human ears can hear dolphins' vocalizations while under the water but cannot hear them well on land is because water is denser than air and air particles travel faster in denser particles.
Denser particles also ensures that the frequency of the waves move faster which in turn produces a faster and louder result.
Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
-
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
-
)
= 0.2(
)
f =
= 150
For air (nair = 1):
= (1.5 - 1)(
-
)
f =
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.
First, we would need to know the decaying isotope.
Next, we use the decay formula
A = Ao e^(-kt)
After determining the remaining amount after two hours, the decay reaction can be used to determine the number of gamma rays released. If the given is in terms of mole, then the total energy is
E = 140n KeV where n is the number of moles of gamma rays released