The normal is an imaginary line at right angles to the plane mirror. Smooth surfaces produce strong echoes when sound waves hit them, and they can act as mirrors when light waves hit them. The waves are reflected uniformly and light can form images.
Answer:
a) always. b) electric field lines are defined by the path positive test charges travel.
Explanation:
By convention, field lines always follow the direction that it would take a positive test charge (small enough so it can´t disrupt the field created by a charge distribution), under the influence of an electric field, at the same point where the test charge is located.
So any positive charge, subject to an electric field influence, moves along the field line that passes through its current position, in the same way that a positive test charge would.
We could say also that the electric force on a positively charged particle is in the same direction as the electric field that produces that force (due to some charge distribution) , which is true, but it doesn´t explain why.
Answer:
Exfoliation or Unloading. As upper rock portions erode, underlying rocks expand. ...
Thermal Expansion. Repeated heating and cooling of some rock types can cause rocks to stress and break, resulting in weathering and erosion. ...
Organic Activity. ...
Frost Wedging. ...
Crystal Growth.
Explanation:
Answer: 2859.78 k
Explanation: By using the law of conservation of energy, the kinetic energy of the meteor equals the heat energy.
Kinetic energy = 1/2mv^2
Heat energy = mcΔθ
Where m = mass of meteor , v = velocity of meteor = 1623 m/s
c = specific heat capacity of meteor (iron) = 460.548 j/kg/k
Δθ = change in temperature of meteor = ?
From law ofconservation of energy, we have that
1/2mv^2 = mcΔθ
By cancelling "m" on both sides, we have that
v^2/2 = cΔθ
v^2 = 2cΔθ
(1623)^2 = 2× 460.548 × Δθ
2634129 = 921.096 × Δθ
Δθ = 2634129 / 921.096
Δθ = 2859.78 k