d=? v=2.5 u=0 and t=5 therefore the formula to be used to find the distance my brother covered is d=1/2(v-u)t
d=1/2(2.5-0)5
=6.15m
Answer:
Atom - the basic particle of matter
Density - calculated from measurements of mass and volume
Motion - calculated from measurements of distance and time
Energy - can change form and move matter
Matter - the scientific word for <em>stuff</em>
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Hope this helps! Please mark brainliest if correct :D
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.
Answer:
density is
Mg/µL
Explanation:
given data
density of nuclear =
kg/m³
1 ml = 1 cm³
to find out
density of nuclear matter in Mg/µL
solution
we know here
1 Mg = 1000 kg
so
1 m³ is equal to
cm³
and here 1 cm³ is equal to 1 mL
so we can say 1 mL is equal to 10³ µL
so by these we can convert density
density =
kg/m³
density =
kg/m³ ×
Mg/µL
density =
Mg/µL
The mass of an object on Earth is the same as its mass on the Moon. The weight is different.
Weight = m * g
Weight ( Moon ) = 40 kg * 1.6 m/s² = 64 N
If the mass of an object on Earth is 40 kg, its mass on the Moon is 40 kg and its weight on the Moon is 64 N.