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2 years ago

If the radius of a coinis 20cm, find itssurface area -

Physics

1 answer:

meriva2 years ago

8 0

Answer:

800 $\pi$ cm²

Explanation:

Given parameters:

radius of the coin = 20cm

Unknown:

Surface area of the coin = ?

Solution:

A coin is made up of two faces;

Surface area = 2(πr²)

Insert the parameters and solve;

Surface area = 2( $\pi x 20^{2}$ )

Surface area = 800 $\pi$ cm²

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A single loop of current is immersed in an externally applied uniform magnetic field of 3 Tesla oriented in the positive y direc

vlabodo [156]

Answer:

mu=12Tm^2

Explanation:

the magnetic moment mu of a single loop is given by:

$\mu = I A B$

where I is the current, B is the magnetic field and A is the area of the loop. By replacing we obtain:

$\mu=(0.5A)(4m*2m)(3T)=12Tm^2$

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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

3 years ago

taurus [48]

Answer:

31,360J

Explanation:

Gravitation potential energy (gpe) is calculated from the formula mgh.

That implies, gpe = mgh

Therefore substituting the values of m and h as given in the question, knowing in mine that the acceleration due to gravity( g) is 9.8 N/kg, will give 31,360J

Never forget to put your SI units, because even if your answer is numerical correct, it will be incorrect because it represents no physical quantity.

5 0

3 years ago

Que cuerpos celestes observó laika durante su viaje

sergejj [24]

Do you want me to translate it?

4 0

2 years ago

A force of 2 kN is applied to an object to make it move 3.6 m in the direction of the force. Select the correct value of work do

vaieri [72.5K]

Answer:

W= F × d

W= 2kn × 3.6

W= 7.2 J

Work is measured in Joules!

4 0

3 years ago

If the radius of a coinis 20cm, find itssurface area -​

If the radius of a coinis 20cm, find itssurface area -