Answer:
when the ground is very hot and the air is cool.
Explanation:
The hot earth warms a layer of air right above the ground. Light is refracted as it passes through the cool air and onto the hot air sheet (bent). A coating of very warm air near the earth bends the light from the sky almost into a U-shaped bend.
Answer:
chicken
Explanation:
you like chicken and want to eat it
Answer:
<h2>C. <u>
0.55 m/s towards the right</u></h2>
Explanation:
Using the conservation of law of momentum which states that the sum of momentum of bodies before collision is equal to the sum of the bodies after collision.
Momentum = Mass (M) * Velocity(V)
BEFORE COLLISION
Momentum of 0.25kg body moving at 1.0m/s = 0.25*1 = 0.25kgm/s
Momentum of 0.15kg body moving at 0.0m/s(body at rest) = 0kgm/s
AFTER COLLISION
Momentum of 0.25kg body moving at x m/s = 0.25* x= 0.25x kgm/s
<u>x is the final velocity of the 0.25kg ball</u>
Momentum of 0.15kg body moving at 0.75m/s(body at rest) =
0.15 * 0.75kgm/s = 0.1125 kgm/s
Using the law of conservation of momentum;
0.25+0 = 0.25x + 0.1125
0.25x = 0.25-0.1125
0.25x = 0.1375
x = 0.1375/0.25
x = 0.55m/s
Since the 0.15 kg ball moves off to the right after collision, the 0.25 kg ball will move at <u>0.55 m/s towards the right</u>
<u></u>
<span>Since frequency and wavelength have inverse relationship. It can be expressed by the equation:
ν.λ = c
Where,
v = frequency of the electromagnetic wave.
λ = it's wavelength
c = the speed of light in a vacuum.
v = 2.00 Ghz x 10^9 Hz / 1 Ghz = 2.00 x 10^9 Hz
that means that in one second it covers 2.00 x 10^9 cycles.
λ = 3.10^8 m/s / 2.00 x 10^9 /s = 1.25E-10 nanometers</span>
The speed of a mechanical wave depends on the mechanical properties
of the medium through which the wave is traveling.
The speed of an electromagnetic wave depends on the electrical properties
of the medium through which the wave is traveling.
It's pretty well unanimous for choice <em>A</em> .