A submarine travels 25 km/h north for 3.2 hours. What is its displacement?

When the C4 key on a piano keyboard is pressed, a string inside the piano is struck by a hammer and begins vibrating back and fo

Anettt [7]

Answer:

Frequency = 260 Hz and wavelength = 1.31 m

Explanation:

Given that,

A hammer begins vibrating back and forth at approximately 260 cycles per second.

(a) The frequency of an object is the number of vibrations per unit time. The frequency of the sound wave is 260 Hz.

(b) The speed of sound in air is 343 m/s. So,

$v=f\lambda\\\\\lambda=\dfrac{v}{f}\\\\\lambda=\dfrac{343}{260}\\\\\lambda=1.31\ m$

Hence, this is the required solution.

8 0

3 years ago

You work for the city water department and need to pump 3400 liters/minute of water from a tank at ground level into a vented (i

umka21 [38]

Answer:

$P_E=46.2778\ kW$

$v=1.804\ m.s^{-1}$

Explanation:

Given:

flow rate of water, $\dot{V}=3400\ L.min^{-1}=3.4\ m^3.min^{-1}$

∵Density of water is 1 kg per liter

∴mass flow rate of water, $\dot{m}=3400\ kg.min^{-1}$

height of pumping, $h=75\ m$

efficiency of motor drive, $\eta=0.9$

diameter of pipe, $D =0.2\ m$

Now the power required for pumping the water at given conditions:

$P=\dot{m}.g.h$

$P=\frac{3400}{60} \times 9.8\times 75$

$P=41650\ W$

Hence the electric power required:

$P_E \times \eta=P$

$P_E \times 0.9=41650$

$P_E=46.2778\ kW$

Flow velocity is given as:

$v=\dot{V}\div a$

where: a = cross sectional area of flow through the pipe

$v=\frac{3.4}{60}\div (\pi.\frac{0.2^2}{4} )$

$v=1.804\ m.s^{-1}$

3 0

3 years ago

Solvents are the substances that dissolve solutes; therefore, solvents are always liquids.

Nina [5.8K]

False, although they are usually a liquid. Solvents can be a solid or gas as well. Also, solutes can be in any state as well.

4 0

2 years ago

A 1300 kg car traveling with a speed of 3.5 m/s executes a turn with a 8.5 m radius of curvature.

Y_Kistochka [10]

Answer:

1.4 m/s/s (2.s.f)

Explanation:

The formula for centripetal acceleration is:

$a=\frac{v^{2} }{r}$ , where v is velocity and r is the radius.

In the question we are given the information that the car has a mass of 1300kg, a velocity of 2.5m/s, and a turn radius of 8.5m which are all the values we need. Therefore we can simply substitute in the values to solve the question:

$a=\frac{3.5^{2} }{8.5} \\a=1.4$

Therefore the centripetal acceleration of the car is 1.4m/s/s. (2.s.f)

Hope this helped!

7 0

3 years ago

Air at the poles tends to flow close to the surface toward the equator. What can you conclude about the characteristics of this

LenaWriter [7]

Answer:

That the polar air has has more pressure than the air at the equator.

Explanation:

5 0

3 years ago