Why does a rock not visibly vibrate?

What type of sound is produced when string vibrates rapidly?

amid [387]

The faster a string vibrates, the higher frequency sound it produces,
and the higher the pitch is that we hear.

8 0

3 years ago

As a bicycle pump inflates a tyre, it pressure rises from 30 kPa to 40 kPa at constant temperature of 30 °C. By assuming the air

MArishka [77]

This question involves the concepts of work done, pressure, and temperature.

The work done per mol of the air is "-724.71 J/mol".

Using the given formula for work done:

$W=RTln\frac{P_1}{P_2}$

where,

W = work done per mol = ?

R = universal gas constant = 8.314 J/mol.k

T = absolute temperature = 30°C + 273 = 303 k

P₁ = initial pressure = 30 KPa

P₂ = final pressure = 40 KPa

Therefore,

$W= (8.314\ J/mol.k)(303\ k)ln\frac{30\ KPa}{40\ KPa}\\$

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Learn more about pressure here:

brainly.com/question/23358029?referrer=searchResults

7 0

3 years ago

A motor-driven winch pulls a 50.0 kg student 5.00 m up the rope at a constant speed of 1.25 m/s. how much power does the motor u

nadya68 [22]

Power is the rate work done given by dividing work done by unit time. It is measured in watts equivalent to J/s.
In this case the force by the student is mg = 490 N (taking g as 9.8m/s²)
Work done is given by force × distance,
Therefore, Power =(force × distance)/ time, but velocity/speed =distance/time
Thus, Power = force × speed/velocity
= 490 N × 1.25
= 612.5 J/S (Watts)
Hence, power will be 612.5 Watts.

7 0

4 years ago

A heat engine accepts 200,000 Btu of heat from a source at 1500 R and rejects 100,000 Btu of heat to a sink at 600 R. Calculate

diamong [38]

To solve the problem it is necessary to apply the concepts related to the conservation of energy through the heat transferred and the work done, as well as through the calculation of entropy due to heat and temperatra.

By definition we know that the change in entropy is given by

$\Delta S = \frac{Q}{T}$