Answer:
<em>UP</em>
Explanation:
heat flows from higher level to lower level
( higher concentration to lower concentration )
and since temperature in above block is less than the lower block, the heat will flow from lower block to higher block .
( Up )
Answer:
Both objects will undergo the same change in velocity
Explanation:
m = Mass of the Earth = 5.972 × 10²⁴ kg
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
r = Radius of Earth = 6371000 m
m = Mass of object
Any object which is falling has only the acceleration due to gravity.
The acceleration due to gravity on Earth is 9.81364 m/s²
So, the speeds of the objects will change at an equal rate of 9.81364 m/s² but the change will be negative when an object is thrown up.
Hence, both objects will undergo the same change in velocity.
Answer:
λ = 5.4196 10⁻⁷m, λ = 541.96 nm this is green ligh
Explanation:
The photoelectric effect was explained by Eintein assuming that the light was made up of particles called photons and these collided with the electrons taking them out of the material.
K = h f -Ф
where K is the kinetic energy of the ejected electrons, hf is the energy of the light quanta and fi is the work function of the material.
The speed of light is related to wavelength and frequency
c = λ / f
f = c /λ
we substitute
K = h c / λ - Φ
for the case that they ask us the kinetic energy of the electons is zero (K = 0)
h c / λ = Ф
λ = h c / Ф
we calculate
λ = 6.63 10⁻³⁴ 3 10⁸ / 3.67 10⁻¹⁸
λ = 5.4196 10⁻⁷m
let's take nm
lam = 541.96 nm
this is green light
Answer:
The wavelength and frequency of light are closely related. The higher the frequency, the shorter the wavelength. Because all light waves move through a vacuum at the same speed, the number of wave crests passing by a given point in one second depends on the wavelength.
Explanation:
The frequency of a light wave is how many waves move past a certain point during a set amount of time -- usually one second is used. Frequency is generally measured in Hertz, which are units of cycles per second. Color is the frequency of visible light, and it ranges from 430 trillion Hertz (which is red) to 750 trillion Hertz (which is violet). Waves can also go beyond and below those frequencies, but they're not visible to the human eye. For instance, radio waves are less than one billion Hertz; gamma rays are more than three billion billion Hertz.Wave frequency is related to wave energy. Since all that waves really are is traveling energy, the more energy in a wave, the higher its frequency. The lower the frequency is, the less energy in the wave. Following the above examples, gamma rays have very high energy and radio waves are low-energy. When it comes to light waves, violet is the highest energy color and red is the lowest energy color. Related to the energy and frequency is the wavelength, or the distance between corresponding points on subsequent waves. You can measure wavelength from peak to peak or from trough to trough. Shorter waves move faster and have more energy, and longer waves travel more slowly and have less energy.Aside from the different frequencies and lengths of light waves, they also have different speeds. In a vacuum, light waves move their fastest: 186,000 miles per second (300,000 kilometers per second). This is also the fastest that anything in the universe moves. But when light waves move through air, water or glass, they slow down. That's also when they bend and refract.
<h3><u>Full Question:</u></h3>
A 2-kg toy car accelerates from 5 to 10 m/s in 2 seconds. Find the applied force.
<h2><u>Answer:</u></h2>
Force applied is 
.
<h3><u>Explanation:</u></h3>
Force is defined as something which changes or tends to change the velocity of a body. And acceleration is defined as the rate of change of velocity of a body per time. Both of them are vector quantities.
The initial velocity of the body = 5 m/s.
The final velocity of the body = 10 m/s.
So the change in velocity = 10 - 5 m/s = 5m/s.
Time period = 2 seconds.
So acceleration =
= 
The force is defined as the product of mass and acceleration of the body.
Mass of body = 2 kg.
So, force applied = 
. =
.
