Hi there!
Acceleration = change in velocity / change in time = Δv/Δt
Thus:
a = (75 - 15)/4 = 60/4 = 15 mi/hr²
Answer:
The potential difference between the plates increases
Explanation:
As we know that the capacitance of the capacitor is given by:
(1)
where
q = charge
C = capacitance
V = Voltage or Potential Difference
Also, the capacitance of a parallel plate capacitor is given as:
(2)
where

A = Area of the plates
D = Separation distance between the plates
Now, from eqn (1) and (2):

Now, from the above eqn we can say that:
Potential difference depends directly on the separation distance between the plates of the capacitor and is inversely dependent on the area of the plates of the capacitor.
Therefore, after disconnecting, if the separation between the plates is increased the potential difference across it also increases.
Answer:
Explanation:
Volume of lead object = volume of aluminium object = V
mass of lead object > mass of aluminium object
When both the objects immersed in water, the buoyant force acting on both the objects.
Buoyant force = Volume immersed x density of water x gravity
As the volume of both the objects is same, so the buoyant force acting on both the objects is same.
So, weight in air of lead object is more than the weight in air of aluminium object.
Answer:
100nm-280nm
Explanation:
Ultraviolet rays (UV) are part of the electromagnetic spectrum. It goes from 10nm to 400nm wavelengths, they are shorter than visible light, thus it's impossible to see by a human eye, and larger than X-rays (used in many medical applications and harmful when long-exposed).
According to its wavelengths, UV can be divided in different types:
UVA: long wave UV (315nm-400nm)
UVB: medium-wave UV (280nm-315nm)
UVC: short wave UV (100nm-280nm)
Therefore, UVC comprises wavelengths between 10nm and 280nm.