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3 years ago

The radius of a conducting wire is doubled .What will be the ratio of its new specific resistance to the old one?

1 answer:

7 0

The equation for the resistance R is: R=ρ*(l/A), where, ρ is electrical resistivity, l is the length of the conductor, and A is the surface area.

The initial surface area is:

A=r²π, then when we double the radius we get:

A₁=(2*r)²π=4*r²π=4*A

Initial resistance is: R=ρ*(l/A).

When we double the radius, resistance is: R₁=ρ*{ l / (4*A) }

The ratio of the new resistance to the old one:

R₁/R=[ρ*(l/A)] / [ ρ* { l / (4*A) } ] = ρ, l and A cancel out and we get:

R₁/R=(1/1)/(1/4)=4/1

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The distance between the ruled lines on a diffraction grating is 1900 nm. The grating is illuminated at normal incidence with a

SashulF [63]

Answer:

3.28 degree

Explanation:

We are given that

Distance between the ruled lines on a diffraction grating, d=1900nm= $1900\times 10^{-9}m$

Where $1nm=10^{-9} m$

$\lambda_2=400nm=400\times10^{-9}m$

$\lambda_1=700nm=700\times 10^{-9}m$

We have to find the angular width of the gap between the first order spectrum and the second order spectrum.

We know that

$\theta=sin^{-1}(\frac{m\lambda}{d})$

Using the formula

m=1

$\theta_1=sin^{-1}(\frac{1\times700\times 10^{-9}}{1900\times 10^{-9}})$

$\theta=21.62^{\circ}$

Now, m=2

$\theta_2=sin^{-1}(\frac{2\times400\times 10^{-9}}{1900\times 10^{-9}})$

$\theta_2=24.90^{\circ}$

$\Delta \theta=\theta_2-\theta_1$

$\Delta \theta=24.90-21.62$

$\Delta \theta=3.28^{\circ}$

Hence, the angular width of the gap between the first order spectrum and the second order spectrum=3.28 degree

6 0

2 years ago

Derek owns a farm that produces soybeans, avocados, and pecans. What is the word used to describe these items?

Novosadov [1.4K]

Answer:

crops

Explanation:

dairy are milk products and those aren’t

live stock is domesticated farm animals raised to produce resources

non-perishables are canned food and dried food. they can last a long time. they don’t need to be refrigerated or

7 0

2 years ago

Read 2 more answers

Which of the following demonstrates a translation?

vampirchik [111]

A spinning wheel and the blade of a kitchen blender both illustrate rotation.

A child swinging on a swing illustrates oscillation, or 'harmonic' motion.

A balloon being blown up is an example of dilation or inflation.

A sliding hockey puck demonstrates the concept of translation.

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2 years ago

Read 2 more answers

2. A truck speeds up from a velocity of 6 m/s to 14 m/s in 4 seconds. What is the trucks acceleration? SHOW YOUR WORK

zavuch27 [327]

As it is given here

initial speed is

$v_i = 6 m/s$

After 4 seconds the final speed is

$v_f = 14 m/s$

so here we can use the formula of acceleration using kinematics

$a = \frac{v_f - v_i}{t}$

$a = \frac{14 - 6}{4}$

$a = 2 m/s^2$

so here it will accelerate at 2 m/s^2 rate.

As it is given here

initial it starts from rest

$v_i = 0 m/s$

After 2.5 seconds the final speed is

$v_f = 15 m/s$

so here we can use the formula of acceleration using kinematics

$a = \frac{v_f - v_i}{t}$

$a = \frac{15 - 0}{2.5}$

$a = 6 m/s^2$

so here it will accelerate at 6 m/s^2 rate.

i think question is not correct as in first line it is saying about a bag of trash and then in next line it is asking for the position of Jumper and bridge.

7 0

2 years ago

Sandi believes that people who eat at McDonald's are overweight, so she decides to do a naturalistic observation of people who e

lubasha [3.4K]

Answer:

observer bias

Explanation:

Based on the information provided within the question the thing that should concern us the most about Sandi's observations is Observer Bias. This term refers to the tendency of a researcher to see what they want as opposed to what is actually happening. This can be said because of Sandi's belief that McDonald clients are all overweight, by having this belief before actually having come to this conclusion with a series of tests, it might lead her to believe this to be true regardless of what she observes during the experiment.

I hope this answered your question. If you have any more questions feel free to ask away at Brainly.

6 0

2 years ago