Physics, 01.11.2019 02:31, maxicanofb0011

1. wood conducts heat very poorly—it has a very low conductivity. does wood still have a low conductivity if it is hot? a. yes
b. no2. could you quickly and safely grasp the wooden handle of a pan from a hot oven with your bare hand? a. yes
b. no3. although the pan handle is hot, is much heat conducted from it to your hand if you grasp it briefly? a. yes
b. no4. why would it be a poor idea to do the same with an iron handle? a. yes
b. noexplain.

Answers: 2

Show answers

Answers

answered: SupremeNerdx

1. A.Yes

2. A.Yes

3. A.Yes

4. A.Yes

Explanation:

1. Wood conducts heat poorly, and yes it has the same property of conductivity even when it is hot. Its thermal conductivity does not changes with temperature if it is uniformly dry and uniformly dense. Its thermal conductivity increases with density and moisture content; thus, light & dry woods are better insulators.

2. Yes, one can grasp quickly and safely the wooden handle of a pan from a hot oven with ones bare hand for a short time.

3. Yes, although the pan handle is hot, not much heat conducted from it to our hand if we grasp it briefly because it has low value of thermal conductivity.

In other words it has high resistance to the flow of heat via conduction. So, the rate of heat transfer is slow, providing us a considerable frame of time to hold it safely.

The explanation can be justified by the Fourier's Law of Thermal Conduction:

Mathematically:

$q=-kA\frac{dT}{dx}$

where:

q= rate of heat transfer through conduction in the material of thermal conductivity kdT= temperature difference across the ends of material through which the heat is being conducteddx= thickness of the ends of material across which the heat is being conducted.

-ve sign is to express that the direction of heat flow is in the direction of decreasing temperature.

4. Yes, it would be a poor idea to do the same with an iron handle because it has higher thermal conductivity which means that more heat is transferred in a short span of time that can cause burn to the bare hands.

answered: Guest

Hello how was your day? ? i hope it was good

answered: Guest

we have been given a quadratic function $f(x)=(x-5)^{2} +2$ and we need to restrict the domain such that it becomes a one to one function.

we know that vertex of this quadratic function occurs at (5,2).

further, we know that range of this function is $[2,\infty)$ .

if we restrict the domain of this function to either $(-\infty,5]$ or $[5,\infty)$ , it will become one to one function.

let us know find its inverse.

$y=(x-5)^{2}+2$

upon interchanging x and y, we get:

$x=(y-5)^{2}+2$

let us now solve this function for y.

$(y-5)^{2}=x-2\\ y-5=\pm \sqrt{x-2}\\ y=5\pm \sqrt{x-2}\\$

hence, the inverse function would be $f^{-1}(x)=5+\sqrt{x-2}$ if we restrict the domain of original function to $[5,\infty)$ and the inverse function would be $f^{-1}(x)=5-\sqrt{x-2}$ if we restrict the domain to $(-\infty,5]$ .

Other questions on the subject: Physics

Physics, 21.06.2019 21:30, krystalhurst97

Astudent looks at ocean waves coming into the beach. an ocean wave with more energy will a) have a greater height. b) have a greater period. c) travel toward the beach faster. d) strike the beach with greater frequency.

Answers: 1

continue

Physics, 22.06.2019 12:30, lmolder1329

Consider a 1000 w iron whose base plate is made of 0.5 cm thick aluminum alloy 2024-t6 (ρ = 2770 kg/m3 and cp = 875 j/kg°c). the base plate has a surface area of 0.03 m2. initially, the iron is in thermal equilibrium with the ambient air at 22°c. assuming 90% of the heat generated in the resistance wires is transferred to the plate, determine the minimum time needed for the plate temperature to reach 200°c.

Answers: 1

continue

Physics, 22.06.2019 15:00, chynahgibsonwinfrey

What happens when a rubber rod is rubbed with a piece of fur?

Answers: 1

continue

Physics, 22.06.2019 20:00, rosepotato789

Choose a realistic problem for which these are the correct freebody diagrams. be sure that the answer that the problem requests is consistent with the diagrams shown. choose a realistic problem for which these are the correct freebody diagrams. be sure that the answer that the problem requests is consistent with the diagrams shown. a 1.0 kg block is placed on top of a 2.0 kg block. a horizontal rope pulls the 2.0 kg block across a frictionless floor with a force of 21.0 n. the coefficient between the two blocks is 0.75. does the 1.0 kg block on top slide?

Answers: 3

continue

Do you know the correct answer?

1. wood conducts heat very poorly—it has a very low conductivity. does wood still have a low conduct...