A unit of acceleration needs a unit of length in the numerator
and a squared unit of time in the denominator.
Example: meters / second²
feet / minute²
smoots / hour²
furlongs / fortnight² .
Ideally, in order to completely describe an acceleration vector,
you also need to state a direction.
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Answer:

Explanation:
We need to find the energy for an electron to jump from n = 1 to n = 4.
The energy in transition from 1 state to another is given by :

The difference in energy for n = 1 to n = 4 is:

So, the required energy is equal to
.
Answer:
The energy of photon, 
Explanation:
It is given that,
Voltage of anode, 
We need to find the maximum energy of the photon of the x- ray radiation. The energy required to raise an electron through one volt is called electron volt.

e is charge of electron


So, the maximum energy of the x- ray radiation is
. Hence, this is the required solution.
In this case to find the weight of an object you must use the formula.
W = mg