<span>In the question,' when you are sitting a few feet from the fire, your skin feels warmed. What form of heat transfer are acting to transfer heat from the fire to your skin, the correct option is A, that is, convection and radiation. Heat transfer is defined as the exchange of thermal energy between physical systems. The rate at which the heat is transfer depends on the temprature of the system and the properties of the intervening medium through which the heat is been transfered. There are three basic modes of heat transfer, these are: conduction, convection and radiation. Conduction is defined as the transfer of heat between two bodies through physical contact. When two bodies which have different temprature come in contact, there will be a transfer of heat energy between them until the two of them have the same temprature. Conduction usually occurs in solids and liquids; it occurs in gases also but it is extremely slow. Convection is the process by which heat is transfer in fluids, that is, liquids and gases. This is how convection operates: when a fluid is heated, it expands and it becomes lighter, this makes it to rise upward and move to the cooler part of the container, as it rises, it will be replaced by the unheated surrounding particles. This cycle continues until heat is evenly distributed all through the fluid. There are two types of convection: natural and forced convection. The heating of the earth surface by the sun ray is an example of natural convection while the air conditioner we use at home operates by mean of forced convection. Both conduction and convection require matter for heat transfer. Radiation is the transfer of heat from one place to another through electromagnetic waves. The hot body transfer heat by emitting electromagnetic waves. The properties of the electromagnetic waves depend on the temperature of the body. The higher the temperature the more intense the rate of emission of radiation. Radiation can occur in all objects and does not require matter for heat transfer. The heat of the sun reaches the earth surface by means of radiation. In the question given, as the air surrounding the fire were heated they rise and were replaced by the unheated air particles. The continuation of this cycle makes the heat energy to be transferred to the objects around. Thus, the heat from the fire was transferred via convection and radiation. </span>
Answer:
1.6 s
Explanation:
To find the time in which the potential difference of the inductor reaches 24V you use the following formula:
V_o: initial voltage = 60V
R: resistance = 24-Ω
L: inductance = 42H
V_L: final voltage = 24 V
You first use properties of the logarithms to get time t, next, replace the values of the parameter:
hence, after 1.6s the inductor will have a potential difference of 24V
The average speed will be 2.38×10⁶ m/sec.The average speed of an object indicates the pace at which it will traverse a distance. The metric unit of speed is the meter per second.
<h3>What is the average speed?</h3>
The total distance traveled by an object divided by the total time taken is the average speed.
The speed calculated at any particular instant of time is known as the instantaneous speed.
Given data;
Distance travelled = 4.12x10¹⁶ meter
Time period= 1.73x10¹⁰ sec
The average speed is found as
Hence, the average speed will be 2.38×10⁶ m/sec.
To learn more about the average speed, refer to the link;
brainly.com/question/12322912
#SPJ1
Answer:
331.7m/s
Explanation:
Given parameters:
Initial velocity = 100m/s
Acceleration = 50m/s²
Distance = 1km = 1000m
Unknown:
Final velocity = ?
Solution:
To solve this problem, we have to apply the right motion equation shown below;
v² = u² + 2aS
v is the final velocity
u is the initial velocity
a is the acceleration
S is the distance
Now insert the parameters and solve;
v² = 100² + (2 x 50 x 1000)
v² = 110000
v = √110000 = 331.7m/s
Answer:
Hey
(note you have forgotten your diagram so this may not be what you where hoping for.)
The important discovery that galilao made was that he proved that <em><u>all objects no matter their mass fall at the same rate.</u></em>
That is to say that a bowling ball falls at the same rate as a truck.
