Answer:
Explanation:
Impulse and Momentum
They are similar concepts since they deal with the dynamics of objects having their status of motion changed by the sudden application of a force. The momentum at a given initial time is computed as
When a force is applied, the speed changes to and the new momentum is
The change of momentum is
The impulse is equal to the change of momentum of an object and it's defined as the average net force applied times the time it takes to change the object's motion
Part 1
The T-ball initially travels at 10 m/s and then suddenly it's stopped by the glove. The final speed is zero, so
The impulse is
The magnitude is
Part 2
The force can be computed from the formula
The direction of the impulse the T-ball receives is opposite to the direction of the force exerted by the ball on the glove, thus
As per the question the wavelength of spectral line of the neutral hydrogen atom is 21 cm.
Spectral line of hydrogen atom will be observed when an electron will jump from higher excited to the ground state. If E is the energy of the ground state and E' is the energy of the higher excited state,the energy emitted when electron will jump from higher excited to ground state is E'-E.
As per Planck's quantum theory -
Where f is the frequency of emitted radiation and h is the Planck's constant.Actually this energy emitted is also electromagnetic in nature. We know that all the electromagnetic radiation will move with the same velocity which is equal to the velocity of light.
The velocity of light c= 3×10^8 m/s.Hence the velocity of wave corresponding to this spectral line is 3×10^8 m/s.
We know that velocity of a wave is the product of frequency and wavelength of that corresponding wave. Mathematically we can write it as-
[ is the wavelength of the wave ]
It is given that wavelength =21 cm=0.21 m
The frequency is calculated as -
Hence the antenna will be tuned to a frequency of 14.2857×10^8 Hz
Here Hertz[ Hz] is the unit of frequency.