Conductivity is required for the electric current to flow.
Answer : The correct option is, (D) Surface tension is caused by cohesion between water molecules on the surface.
Explanation :
Surface tension : It is caused by the cohesion between water molecules on the surface or we can say that it is a tension of the surface of liquid caused by the attraction of the particles which are present on the surface layer by the bulk of the liquid, which tends to minimize surface area.
And due to the surface tension phenomena the shape of the water molecule tend to assume a spherical shape to attain the minimum surface area.
Hence. the correct option is, (D) Surface tension is caused by cohesion between water molecules on the surface.
Given Information:
Magnetic field = B = 1×10⁻³ T
Frequency = f = 72.5 Hz
Diameter of cell = d = 7.60 µm = 7.60×10⁻⁶ m
Required Information:
Maximum Emf = ?
Answer:
Maximum Emf = 20.66×10⁻¹² volts
Explanation:
The maximum emf generated around the perimeter of a cell in a field is given by
Emf = BAωcos(ωt)
Where A is the area, B is the magnetic field and ω is frequency in rad/sec
For maximum emf cos(ωt) = 1
Emf = BAω
Area is given by
A = πr²
A = π(d/2)²
A = π(7.60×10⁻⁶/2)²
A = 45.36×10⁻¹² m²
We know that,
ω = 2πf
ω = 2π(72.5)
ω = 455.53 rad/sec
Finally, the emf is,
Emf = BAω
Emf = 1×10⁻³*45.36×10⁻¹²*455.53
Emf = 20.66×10⁻¹² volts
Therefore, the maximum emf generated around the perimeter of the cell is 20.66×10⁻¹² volts
<u>Answer</u>:
The primary method by which the planets have been found around other stars in the galaxy is Kepler Space Telescope.
<u>Explanation</u>:
The primary method by which planets have been found around other stars in our beautiful Galaxy is the Kepler space telescope. Kepler launched Kepler Telescope in 2009 to help to find terrestrial planets super-earth etc.
This is the telescope which measures the amount of light coming from a star and detects a slight variation in brightness as a planet passes in front. Using this technique NASA's Kepler Mission has founded thousands of candidate planet in this world.
Answer:
having or representing the sun as the centre, as in the accepted astronomical model of the solar system.
Explanation:
Heliocentrism is the astronomical model in which the Earth and planets revolve around the Sun at the center of the Universe. Historically, heliocentrism was opposed to geocentrism, which placed the Earth at the center.