Answer:
Please find the answer in the explanation
Explanation:
Friction is a force that opposes motion. One or two of the advantages of friction are break and ability of an object to walk.
Writing yes it is useful because when your writing because friction helps you see what your writing
ii. Rubbing. Yes, it is useful.
friction make it possible for two object to rub each other
iii. Skiing. No. It is not useful because With presence of friction, skiing will not be possible.
iv. Rotating a wheel No. It is not useful because Friction will oppose the rotation of the wheel.
Sample Response: No image will be formed because the rays will not converge to or diverge from a common point.
The velocity of the wave is 40 m/s
Explanation:
The relationship between the velocity of a wave and its frequency and wavelength is given by

where
v is the velocity
f is the frequency
is the wavelength
For the ocean wave in this problem, we have:
(wavelength)
f = 4.0 Hz (frequency)
Therefore, its velocity is

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Frequency heard by listener: fl = ?
frequency of source: fs = 300 Hz
velocity of listener: vl = 16 m/s
velocity of source: vs = 0
<span>velocity of sound in air: c = 344 m/s
</span><span>fl = fs [(c – vl)/c] = 300[(344-16)/344]
</span> =286.04 Hz
If one m³ of that material holds 4,000 kg of it,
then 0.09 m³ holds
(0.09) x (4,000) = 360 kg of it
The force of gravity acting on 360 kg of anything
on the Earth's surface is
(mass) x (gravity)
= (360 kg) x (9.8 m/s²) = 3,528