Choose all the answers that apply.

Find the wavelength λ of the 80.0-khz wave emitted by the bat. express your answer in millimeters.

vfiekz [6]

Answer:

4.29 millimeters

Explanation:

Bats emit ultrasound waves: in air, ultrasound waves travel at a speed of

$v=343 m/s$

The frequency of the waves emitted by this bat is:

$f=80.0 kHz = 80,000 Hz$

Therefore we can find the wavelength of the wave emitted by the bat by using the relationship between speed, frequency and wavelength:

$\lambda=\frac{v}{f}=\frac{343 m/s}{80,000 Hz}=4.29\cdot 10^{-3} m=4.29 mm$

4 0

2 years ago

Provide a reason why houses are painted with dark colours in cold countries.

fenix001 [56]

Answer:

which is necessary to keep the building warm. Light colors reflect the light hence they are wisely used in tropical ...

Here in the US, not all houses are painted dark colors. In years past, it was common for the ...

7 0

2 years ago

Read 2 more answers

Where do earthquake waves originate from? select one:

arsen [322]

The correct answer is C) the focus

6 0

3 years ago

in a certain pinhole camera, the screen is 10 cm from the pinhole. When the pinhole is placed 6 cm away from a tree ,a sharp ima

vagabundo [1.1K]

Answer:

Height of the tree is <u>9.6 cm</u>

Explanation:

We know that, Magnification of an image is written as follows.

$\left(\frac{H_{i}}{H_{o}}\right)=\left(\frac{D_{i}}{D_{o}}\right)$

Where,

$\begin{array}{l}{\mathrm{H}_{0}=\text { height of the object }} \\ {\mathrm{H}_{\mathrm{i}}=\text { height of the image }} \\ {\mathrm{D}_{0}=\text { distance of the object }} \\ {\mathrm{D}_{\mathrm{i}}=\text { distance of the image }}\end{array}$

As per given question,

$\begin{array}{l}{\mathrm{H}_{1}=\text { height of the image }=\text { height of the image of the tree on screen }=16 \mathrm{cm}} \\ {\mathrm{D}_{0}=\text { distance of the object }=\text { distance of the tree from the pinhole }=6 \mathrm{cm}} \\ {D_{1}=\text { distance of the image }=\text { distance of the image from the pinhole }=10 \mathrm{cm}} \\ {\mathrm{H}_{0}=\text { height of the object }=\text { height of the tree }}\end{array}$

Substitute the values in the above formula,

$\begin{array}{l}{\left(\frac{H_{i}}{H_{o}}\right)=\left(\frac{D_{i}}{D_{o}}\right)} \\ {\left(\frac{16}{H_{o}}\right)=\left(\frac{10}{6}\right)} \\ {\mathrm{H}_{\mathrm{o}}=\left(\frac{16 \times 6}{10}\right)} \\ {\mathrm{H}_{\mathrm{o}}=9.6 \mathrm{cm}}\end{array}$

Height of the tree is 9.6 cm.

8 0

2 years ago

A bar on a hinge starts from rest and rotates with an angular acceleration α = 15+4t, where α is in rad/s2 and t is in seconds.

Arisa [49]

Answer:

230.53°

Explanation:

α = angle in rad / t^2

t =2mins = 2 × 60 = 120sec.

α = angle in rad / 2^2

α = angle in rad / 16

15+4(2) = angle in rad /4

23 = angle/4

23× 4 = angle in radian

92 = angle in radian

But π rad = 180°

1 rad = 180 /π

Therefore

92 rad = 92 ×180/π = 5270.53°

This value is far more so we subtract from 360° continuously till we get a value less than 360°

5270.53- (360×14) =5270.53- 5040

230.53°

3 0

2 years ago