What is the impulse needed to stop a 45-kg boy who is running at 6 m/s in 3 seconds?

The human eye can readily detect wavelengths from about 400 nm to 700 nm. If white light illuminates a diffraction grating havin

nadya68 [22]

Answer:

The range of angles is from 17.50° to 31.76°

Explanation:

The diffraction grid equation is as follows:

$dsen\theta=m\lambda$

Clearing for $\theta$

$sen\theta=\frac{m\lambda}{d}$

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

where $\theta$ is the angle, $m$ is the order, in this case $m=1$ , $\lambda$ is the wavelength, and $d$ is defined as follows:

$d=\frac{1}{resolution}$

and since the resolution is 750 lines/mm wich is the same as $750lines/1x10^{-3}m$

$d$ will be:

$d=\frac{1}{750lines/1x10^{-3}m}=\frac{1x10^{-3}m}{750lines}=1.33x10^{-6}m$

wich is the distance between each line of the diffraction grating.

substituting the values for $m$ and $d$ :

$\theta=sen^{-1}(\frac{(1)\lambda}{(1.33x10^{-6}m)})$

And we need to find two angle values: one for when the wavelength is 400nm and one for when it is 700 nm. So we will get the angle range

$\theta=sen^{-1}(\frac{(400x10^{-9})}{(1.33x10^{-6}m)})=17.50$

and

$\theta=sen^{-1}(\frac{(700x10^{-9})}{(1.33x10^{-6}m)})=31.76$

The range of angles is from 17.50° to 31.76°

3 0

3 years ago

Calcium-51 has a half-life of 4.5 days. Only 0.75 gram remains of a sample that was initially 12 grams. How old is the sample of

Over [174]

How many times did the original sample lose 50% of its radioactivity ?

-- Start with. . . . . . . . . . . . 12 grams.
-- Lose half of it once. . . . . . 6 grams left.
-- Lose half of it again . . . . . 3 grams left.
-- Lose half of it again . . . . . 1.5 grams left.
-- Lose half of it again . . . . . 0.75 gram left.

-- How many times did it lose half ? 4 times.

-- How long does it take to lose half ? 4.5 days.
(That's why it's called the 'half-life'.)

-- How long did it take to lose half, 4 times ?

(4 x 4.5 days) = 18 days .

6 0

3 years ago

Read 2 more answers

A solid sphere has a temperature of 614 K. The sphere is melted down and recast into a cube that has the same emissivity and emi

krok68 [10]

Answer:581.87 K

Explanation:

Given

Sphere is melted to form a square

Let the radius of sphere be r and square has a side a

Therefore

$\frac{4\pi}{3}r^3=a^3$