Which way does heat travel? Explain your answer.

A piece of toast weighing 8 grams is flying through the air at 15

Ket [755]

The kinetic energy of toast is 0.06 J.

Explanation:

Kinetic energy is the way to determine the energy released when an object is in motion. In other times, it can be the energy required to move any object and to make it in motion.

As the mass of the toast is given as 8 g and speed is given as 15 m/s, if we ignore the friction caused by air molecules. Then the kinetic energy is the product of mass and square of velocity.

K.E. = $\frac{1}{2}$ × mass × v²

Kinetic energy = $\frac{1}{2} \times \frac{8}{1000} \times 15$

Since, the weight is given in grams , it needed to be converted into kg.

Kinetic energy = 0.06 J

Thus, the kinetic energy of toast is 0.06 J.

6 0

3 years ago

A ball of 12 kg is attached to a string of 0.8 meter spun at 4

lesantik [10]

Answer:

240 N

Explanation:

6 0

3 years ago

Using 0.500 g of nichrome, you are asked to fabricate a wire with uniform cross-section. The resistance of the wire is 0.673 Ω.

mojhsa [17]

Explanation:

Given that,

Mass of Nichrome, m = 0.5 g

The resistance of the wire, R = 0.673 ohms

Resistivity of the nichrome wire, $\rho=10^{-6}\ \Omega -m$

Density, $d=8.31\times 10^3\ kg/m^3$

(A) The length of the wire is given by using the definition of resistance as :

Volume,

$V=A\times l\\\\A=\dfrac{V}{l}\\\\Since, V=\dfrac{m}{d}\\\\V=\dfrac{m}{d}\\\\V=\dfrac{0.5\times 10^{-3}}{8.31\times 10^3}\\\\V=6.01\times 10^{-8}\ m^3$

Area,

$A=\dfrac{V}{l}\\\\A=\dfrac{6.01\times 10^{-8}}{l}$ ....(1)

$R=\rho \dfrac{l}{A}\\\\l=\dfrac{RA}{\rho}\\\\l=\dfrac{0.673\times 6.01\times 10^{-8}}{l\times 10^{-6}}\\\\l=0.201\ m$

(b) Equation (1) becomes :

$A=\dfrac{6.01\times 10^{-8}}{l}\\\\A=\dfrac{6.01\times 10^{-8}}{0.201}\\\\\pi r^2=3\times 10^{-7}\\\\r=\sqrt{\dfrac{3\times 10^{-7}}{\pi}} \\\\r=3.09\times 10^{-4}\ m$

Hence, this is the required solution.

5 0

4 years ago

Which parts of Dalton’s atomic theory had to be revised

eduard

The indivisibility of an atom was proved wrong an atom can be further subdivided into protons, neutrons and electrons. However an atom is the smallest particle that takes part in chemical reactions

7 0

3 years ago

A distant galaxy is determined to be 150 million light years distant and moving away from us; using the Hubble law determine its

dlinn [17]

Your question kind of petered out there towards the end and you didn't specify
the terms, so I'll pick my own.

The "Hubble Constant" hasn't yet been pinned down precisely, so let's pick a
round number that's in the neighborhood of the last 20 years of measurements:

 70 km per second per megaparsec.

We'll also need to know that 1 parsec = about 3.262 light years.

So the speed of your receding galaxy is

 (Distance in LY) x (1 megaparsec / 3,262,000 LY) x (70 km/sec-mpsc) =

 (150 million) x (1 / 3,262,000) x (70 km/sec) =

 3,219 km/sec in the direction away from us (rounded)

4 0

3 years ago