Answer:

Explanation:
If we have a periodic wave we need to satisfy the following basic relationship:

From the last formula we see that the velocity is proportional fo the frequency.
For this case we have the following info given by the problem:

We know that the frequency is the reciprocal of the period so we have this formula:

And if we replace we got:

Now since we have the value for the wavelength we can find the velocity like this:

And if we convert this into cm/s we got:

Answer:
A kilowatt (kW) is a unit of power.
Explanation:
The power of an object is given by :

Here,
E is the energy required
t is time
The SI unit of power is Watts and the SI unit of energy is Joule. the commercial unit of energy is kilowatt per hour.
Option (1) : A kilojoule (kJ) is a unit of power is incorrect.
Option (2) : A gigawatt (GW) is a unit of energy is incorrect.
Option (3) : A watt (W) is a unit of energy is incorrect.
Option (4) : A kilowatt x hour per year (kWh/yr) is a unit of energy is incorrect.
Option (4) : A kilowatt (kW) is a unit of power is correct.
Hence, the correct option is (d).
A
The class lever that take that is first class lever which is A
Answer:
"332.8 m/s" is the right solution.
Explanation:
The given values are:
Wavelength,

Frequency,

As we know,
⇒ 
or,
⇒ 
By putting the given values in the above relation, we get
⇒ 
⇒ 