Mass lost = weight of oxygen = 6.75 - 6.12 = 0.63 g
0.63 g / 16.0 g/mole = 0.0394 moles O
6.12 g / 207.2 g/mole = 0.0295 moles Pb
Ratio being roughly 3:4, the empirical formula is Pb3O4 (which is one of the mixed oxides of lead).
Answer:
Car first should be 30.13 m behind the second car.
Explanation:
Given that,
Constant speed = 108.5 Km/hr
Time = 1 sec
Let the distance covered by second car S and by first car S'
We need to calculate the distance covered by second car
Using equation of motion
.....(I)
The distance covered by first car to avoid collision

Put the value into the formula
...(II)
We need to calculate the distance covered by first car
Using equation (I) and (II)

Put the value into the formula


Hence, Car first should be 30.13 m behind the second car.
Explanation:
Given that,
Wavelength of the photon, 
Work function of the metal, 
We need to find the maximum kinetic energy of the ejected electrons. It can be calculated using Einstein's photoelectric equation as :






or

So, the maximum kinetic energy of the ejected electrons is 3 ev. Hence, this is the required solution.
Answer:
The last option is correct
ΔT1 = 4 sec ΔT2 = 4 sec ΔT3 = 4 sec
S = V0 t + 1/2 a t^2
S1 = 1/2 a t^2 = 8 a where V0 is the speed at the start of the interval
During any interval (of 4 sec) the particle travels 1/2 a t^2 = 8 a due to its acceleration - and you need to include the speed at the start of the interval
S1 = 8a
S2 = 8 a + 8 a = 16 a
S3 = 16 a + 8 a = 24 a
Note: V2 = V1 + a t for any interval
V2 - V1 = V1 + a t - V1 = a t
and a = (V2 - V1) / t = a the speed increase is constant during the interval
It changes because radiation always differs in the atmosphere because of the nuclear plants and of pollution around us. Even though it is indoors.