First of all, we can calculate the frequency of the photon, which is related to the wavelength by the following equation:
where c is the speed of light and
is the photon wavelength. Substituting into the formula, we find the frequency
Now we can find the energy of the photon with the following equation:
where h is the Planck constant. Substituting numbers, we find
Answer:
10 kilograms
Explanation:
The formula for mass
mass (kg)= momentum ( p) divided by velocity (v)
therefore this translates to 50 divided by 5
which gives the final answer as <u>10kgs</u>
Question :
If a body acquires a charge of -0.02 C, has it gained or lost electrons? Many?
Solution :
We know, charge gained is shown by negative sign.
Since, charged acquired is given as -0.02 C .
Therefore, it is body has gained electrons.
Now, number of electrons is given by :
Hence, this is the required solution.
Answer:
2.43J
Explanation:
Given parameters:
Mass of the arrow = 0.155kg
Velocity = 31.4m /s
Unknown:
Kinetic energy when it leaves the bow = ?
Solution:
The kinetic energy of a body is the energy in motion of the body;
it can be derived using the expression below:
K.E = 
m v²
m is the mass
v is the velocity
Solve for K.E;
K.E = x 0.155 x 31.4 = 2.43J
Sound source is at rest, you are moving with velocity v, f = frequency, c = speed of sound:
f = f0(1 + v/c)
115 = 100(1 + v/343)
115 = 100 + 100v/343
15 = 100v/343
v = 15*343/100
<span>
v = 51,45 m/s </span>
