A car travels between 100-mile and 25-mile markets on a highway in 3 hours. The average speed of the car during the interval is

What is the energy of an electromagnetic wave that has a frequency of

sukhopar [10]

Answer:

$Energy, \; E = 2.6504 * 10^{-34} \; Joules$

Explanation:

Given the following data;

Frequency = 4.0 x 10⁹ Hz

Planck's constant, h = 6.626 x 10-34 J·s.

To find the energy of the electromagnetic wave;

Mathematically, the energy of an electromagnetic wave is given by the formula;

E = hf

Where;

E is the energy possessed by a wave.

h represents Planck's constant.

f is the frequency of a wave.

Substituting the values into the formula, we have;

$Energy, \; E = 4.0 x 10^{9} * 6.626 x 10^{-34}$

$Energy, \; E = 2.6504 * 10^{-34} \; Joules$

8 0

2 years ago

How long must a simple pendulum be if it is to make exactly one swing per four seconds? (That is, one complete oscillation takes

cricket20 [7]

Answer:

Length of the pendulum will be 3.987 m

Explanation:

We have given time period of the pendulum T = 8 sec

Acceleration due to gravity $g=9.81m/sec^2$

We have to find the length of the simple pendulum

We know that time period of the simple pendulum is given by

$T=2\pi \sqrt{\frac{l}{g}}$

$8=2\times 3.14 \sqrt{\frac{l}{9.81}}$

$l=3.987m$

So length of the pendulum will be 3.987 m

3 0

2 years ago

Water enters the constant 130-mm inside-diameter tubes of a boiler at 7 MPa and 65°C and leaves the tubes at 6 MPa and 450°C wit

snow_lady [41]

The inlet velocity is 1.4 m/s and inlet volume is 0.019 m³/s.

Explanation:

When water entering the tube of constant diameter flows through the tube, it exhibits continuity of mass in the hydrostatics. So the mass of water moving from the inlet to the outlet tend to be same, but the velocity may differ.

As per mass flow equality which states that the rate of flow of mass in the inlet is equal to the product of area of the tube with the velocity of the water and the density of the tube.

Since, the inlet volume flow is measured as the product of velocity with the area.

Inlet volume flow=Inlet velocity*Area*time

And the mass flow rate is

Mass flow rate in the inlet=density*area*inlet velocity*time

Mass flow rate in the outlet=density*area*outlet velocity*time

Since, the time and area is constant, the inlet and outlet will be same as

(Mass inlet)/(density*inlet velocity)=Area*Time

(Mass outlet)/(density*outlet velocity)=Area*Time

As the ratio of mass to density is termed as specific volume, then

(Specific volume inlet)/(Inlet velocity)=(Specific volume outlet)/(Outlet velocity)

Inlet velocity= (Specific volume inlet)/(Specific volume outlet)*Outlet velocity

As, the specific volume of water at inlet is 0.001017 m³/kg and at outlet is 0.05217 m³/kg and the outlet velocity is given as 72 m/s, the inlet velocity

is

$Inlet velocity = \frac{0.001017}{0.05217}*72 =1.4035 m/s$