A metre rod on wedge is example of unstable equilibrium.why

A truck moving at 45 m/s passes a police car moving at 36 m/s in the opposite direction. if the frequency of the siren is 500 Hz

elena-14-01-66 [18.8K]

Answer: observed frequency (f') = 511.97Hz

Explanation: when there is a relative motion between an observer and a sound source, the frequency of sound wave perceived by the observer is different from the frequency of originally sent out by the sound source.

This is called Doppler effect and given mathematically below as

f' = (v + v') /(v- vs) * f

f' = observed frequency

v = speed of sound in air = 340m/s

v' = velocity of observer= 45m/s

vs = velocity of source relative to observer = - 36m/s ( the negative sign came as a result of the fact that the velocity of the source is in opposite direction to the velocity of the observer)

f = original frequency of sound source = 500Hz

f' = (340 + 45)/{340 -(-36)} * 500

f' = 385/ (340 + 36) * 500

f' = 385/ 376 * 500

f' = 1.0239 * 500

f' = 511.97Hz

7 0

3 years ago

Whats quantum physics?

krek1111 [17]

Answer:

How atoms work and how biology and chemistry work.

Explanation:

8 0

2 years ago

Explain why an equation may be homogenous with respect to its unit but still be incorrect

natima [27]

When both sides of an equation give the same units, same numerical values, and same concept we refer to the equation as being correct. ... Removing constants from correct equations make them homogeneous but incorrect.

6 0

2 years ago

The density of gasoline is 730 kg/m3 at 0°C. Its average coefficient of volume expansion is 9.60 10-4(°C)−1. Assume 1.00 gal of

kipiarov [429]

Answer: 0.4911 kg

Explanation:

We have the following data:

$\rho_{0\°C}= 730 kg/m^{3}$ is the density of gasoline at $0\°C$

$\beta=9.60(10)^{-4} \°C^{-1}$ is the average coefficient of volume expansion

We need to find the extra kilograms of gasoline.

So, firstly we need to transform the volume of gasoline from gallons to $m^{3}$ :

$V=8.50 gal \frac{0.00380 m^{3}}{1 gal}=0.0323 m^{3}$ (1)

Knowing density is given by: $\rho=\frac{m}{V}$ , we can find the mass $m_{1}$ of 8.50 gallons:

$m_{1}=\rho_{0\°C}V$

$m_{1}=(730 kg/m^{3})(0.0323 m^{3})=23.579 kg$ (2)

Now, we have to calculate the factor $f$ by which the volume of gasoline is increased with the temperature, which is given by:

$f=(1+\beta(T_{f}-T_{o}))$ (3)

Where $T_{o}=0\°C$ is the initial temperature and $T_{f}=21.7\°C$ is the final temperature.

$f=(1+9.60(10)^{-4} \°C^{-1}(21.7\°C-0\°C))$ (4)

$f=1.020832$ (5)

With this, we can calculate the density of gasoline at $21.7\°C$ :

$\rho_{21.7\°C}=730 kg/m^{3} f=(730 kg/m^{3})(1.020832)$

$\rho_{21.7\°C}=745.207 kg/m^{3}$ (6)

Now we can calculate the mass of gasoline at this temperature:

$m_{2}=\rho_{21.7\°C}V$ (7)

$m_{2}=(745.207 kg/m^{3})(0.0323 m^{3})$ (8)

$m_{2}=24.070 kg$ (9)

And finally calculate the mass difference $\Delta m$ :

$\Delta m=m_{2}-m_{1}=24.070 kg-23.579 kg$ (10)

$\Delta m=0.4911 kg$ (11) This is the extra mass of gasoline

6 0

3 years ago

What causes earth to have a complete year

RUDIKE [14]

Answer:

Earth's Tilt and The Seasons. Earth, like all of the planets in the Solar System, travels around the Sun. One complete orbit of the Sun is known as a year and it takes Earth 365 days, 5 hours, 48 minutes and 46 seconds to complete an orbit. The changing seasons are caused by the fact that Earth is tilted. please vote me brainliest i can't message no one cuz i haven't got enough points i'm desperate.

Explanation:

7 0

3 years ago