Answer:
Mass, m = 1.51 grams
Explanation:
It is given that,
The circumference of Aluminium cylinder, C = 13 mm = 1.3 cm
Length of the cylinder, h = 4.2 cm
We know that the density of the Aluminium is 2.7 g/cm³
Circumference, C = 2πr
Density is equal to mass per unit volume.
m is mass of the cylinder
V is the volume of the cylinder
So,
So, the mass of the cylinder is 1.51 grams.
Answer:
Use the activity formula,
T1/2 = 4.468 x 10^9 yr x 365 x 24 x 3600 = 1.409 x 10^17 sec
l = ln(2)/T1/2 = ln(2)/1.409 x 10^17 = 4.91932697 x 10^-18 s-1
DN/Dt = lN, 265 = 4.91932697 x 10^-18 x N
<u><em>N = 5.38 x 10^19 nuclei</em></u>
Answer: Between 1 and 2.
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
............(1)
where,
a = amount of reactant left after n-half lives = 40
= Initial amount of the reactant = 100
n = number of half lives
Putting in the values we get:
taking log on both sides
Thus half-lives that have elapsed is between 1 and 2
In a flame photometric analysis, salt solution is first vaporized using the heat of flame, followed by this electrons from valance shell gets excited from ground state to excited state. Followed by this de-excitation of electron bring backs electrons to ground state. This process is accompanied by emission of photon. The photon emitted is characteristic of an element, and number of photons emitted can be used for quantitative analysis.
<span>Following are the investigative question that you can answer by doing this experiment.
</span>1) What information can be obtained from the colour of flame?
2) <span>State the relationship between wavelength, frequency, and energy?
</span><span>3) Can you identify the metal present in unknown sample provided?
4) How will you identify amount of metal present in sample solution?
5) </span><span>Why do different chemicals emit light of different colour?</span><span>
</span>
Answer:
The switch is used to <u>disconnect</u> or <u>connect</u> an electrical circuit. When the switch is on, the circuit is <u>complete</u>, and when the switch is <u>off</u>, the circuit is open. Electrical current exists in the circuit when it is closed, but when it is open, there is no <u>electrical</u> current in the circuit. The switch determines whether the circuit is open and closed.
