The first experiment that was made to attempt to measure the speed of light involved detonating gunpowder by Isaac Beeckman. He declared that his experiment was inconclusive. Galileo also tried to measure the speed of light using two lanterns placed across each other. The next experiment involved planets where Ole Romer based his calculation on its movements. The final calculations were derived from different theories by different scientists including Maxwell until it ended up with the exact value for the speed of light.
It all depends on what kind of wave, and what kind of medium.
For mechanical waves, like sound and earthquakes, the speed
is determined by the mechanical properties of the medium, like
density and stiffness.
For electromagnetic waves, like radio and light, the speed is
determined by the electrical properties of the medium, like
magnetic permeability and electrostatic permittivity.
That's a big part of the reason why sound and light travel
at different speeds through air, water, and jello.
For a floating object, the buoyancy force is equal to the gravity force on the object. Hence, the buoyancy force doesn't change with a denser fluid. Instead the displaced volumedecreases to cancel out the effect of the increased fluid density.
Answer:
ΔL = 0.66 m
Explanation:
The change in length on an object due to rise in temperature is given by the following equation of linear thermal expansion:
ΔL = αLΔT
where,
ΔL = Change in Length of the bridge = ?
α = Coefficient of linear thermal expansion = 11 x 10⁻⁶ °C⁻¹
L = Original Length of the Bridge = 1000 m
ΔT = Change in Temperature = Final Temperature - Initial Temperature
ΔT = 40°C - (-20°C) = 60°C
Therefore,
ΔL = (11 x 10⁻⁶ °C⁻¹)(1000 m)(60°C)
<u>ΔL = 0.66 m</u>
Current is defined as the rate of charge flowing a point every second. Having a current of 1 Ampere signifies 1 Coulomb is flowing in a circuit every second. It is measured by the use of an ammeter which is positioned in series to the component to be measured. The current in the problem is calculated as follows:
I = 2.0 x 10^-4 C / 5.0 x 10^-5 s
<span>I = 4 A</span>
