Answer:
Conduction is usually faster in certain solids and liquids than in gases. Materials that are good conductors of thermal energy are called thermal conductors. Metals are especially good thermal conductors because they have freely moving electrons that can transfer thermal energy quickly and easily.
Heat transfer by convection happens through the air, and there are millions of minuscule air spaces between the fibers. Heat transfer by radiation is also slow since one fiber must radiate its heat to another.
When we give heat then kinetic energy is increase and this heat is transferred from hot metal to cold metal through this free electrons. As in insulator the free electrons are negligible so that the heat is not transferred from hot junction to cold junction due to absence of this free electrons.
Explanation:
maek me as brainliest
The first two choices are both false, but the <em>second one</em> is the falser one.
All electricity sources do <em>not</em> have the same voltage. The outlet in your bedroom wall supplies 120 volts, but the USB port on your laptop only supplies 5 volts, and the battery in your cellphone only supplies 3.7 volts.
Answer:
The index of refraction of quartz for violet light is 1.47.
Explanation:
It is given that, a narrow beam of white light is incident on a sheet of quartz.
The beam disperses in the quartz, with red light at an angle, 
wrt to the normal and violet light traveling at an angle of 
The index of refraction of quartz for red light is 1.45.
We need to find the index of refraction of quartz for violet light.
Using Snell's law of red light as follows :
Here,
is the refractive index of air
is the angle of incidence
We can find the value of angle of incidence as follows :
Now again using Snell's law for violet light as follows :
So, the index of refraction of quartz for violet light is 1.47.
Answer:
option E
Explanation:
given,
angular speed of bicycle tire ()= 3.80 rad/s
time period = 2.35 s
tire stops and spun in opposite direction with angular velocity = 3.80 rad/s
average angular acceleration
initial angular speed = ω₀ = - 3.80 rad/s
final angular speed = ω₁ = 3.80 rad/s
change in angular velocity
average angular acceleration
approximately equal to 3.4 rad/s²
the correct answer is option E
Answer:
3.72 m/s²
Explanation:
Horizontal component of the force applied = Fcosθ = 86 cos 30 = 74.478 N
Force = mass × acceleration = 74.478 N
ma = 74.478 N
a = 74.478 / 20 since friction can be neglected = 3.72 m/s²
