Answer:
a)V= 0.0827 m³
b)P=181.11 x 10² N/m²
Explanation:
Given that
m = 81.5 kg
Density ,ρ = 985 kg/m³
As we know that
Mass = Volume x Density
81.5 = V x 985
V= 0.0827 m³
The force exerted by weight = m g
F= m g= 81.5 x 10 = 815 N ( Take ,g= 10 m/s²)
Area ,A= 4.5 x 10⁻² m²
The Pressure P
P=181.11 x 10² N/m²
Answer: a) 3.85 days
b) 10.54 days
Explanation:-
Expression for rate law for first order kinetics is given by:
where,
k = rate constant = ?
t = time taken for decomposition = 3 days
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process =
First we have to calculate the rate constant, we use the formula :
Now put all the given values in above equation, we get
a) Half-life of radon-222:
Thus half-life of radon-222 is 3.85 days.
b) Time taken for the sample to decay to 15% of its original amount:
where,
k = rate constant =
t = time taken for decomposition = ?
a = let initial amount of the reactant = 100 g
a - x = amount left after decay process =
Thus it will take 10.54 days for the sample to decay to 15% of its original amount.