Simply, apply the formula

and insert the values of m = mass, v = velocity and E = Energy.
The result will be

, m = 1 kg
Answer:
Explanation:
We know the frequency and the velocity, both of which have good units. All we have to do is rearrange the equation and solve for
λ
:
λ
=
v
f
Let's plug in our given values and see what we get!
λ
=
340
m
s
440
s
−
1
λ
=
0.773
m
Answer:
The force exerted by the earth on a body is called gravitational of a body.
i think this is the answer
Answer:
The beam used is a negatively charged electron beam with a velocity of
v = E / B
Explanation:
After reading this long statement we can extract the data to work on the problem.
* They indicate that when the beam passes through the plates it deviates towards the positive plate, so the beam must be negative electrons.
* Now indicates that the electric field and the magnetic field are contracted and that the beam passes without deviating, so the electric and magnetic forces must be balanced

q E = qv B
v = E / B
this configuration is called speed selector
They ask us what type of beam was used.
The beam used is a negatively charged electron beam with a velocity of v = E / B
Answer:
f>1000Hz and wavelength=0.343 m
Explanation:
We are given that
Frequency of stationary siren,f=1000 Hz
Wavelength of stationary sound,
When a observer is moving towards the siren then the frequency increases.
Therefore,an observer who is moving towards the siren measure a frequency >1000 Hz.
The wavelength depends upon the speed of source.
But we are given that siren is stationary.
Therefore, source is not moving and then the wavelength remains same.
f>1000Hz and wavelength=0.343 m