The standard measurement system used by the scientists is called: International System Of Units, or SI. The units of measurement of a few physical quantities are considered to be base units. (Also do you need the base units too cuz I can help you with that) :)
<span>distance = 360 degrees and the time= 24 hours=1 day
</span><span>Calculate the circumference using D of 16 millions miles and pi
C=50.3 million miles. Using your hint v=(50.3 10^6)/(365.25 x 24 hrs)
</span>
radius of 98 million miles or a diameter of 196 million miles, giving a circumference of 615.75 million miles using the d=rt equation,
v=615.75 million/(365.24 days)=1.69 million miles per day, or .07 million miles per hour.
Answer:
Explanation:
Lead has an half life of 43.5 seconds
The radioactive decay law says
N(t) = No•2^(-t / t½)
Hence, the percent of a sample of the Lead-214 isotope that decay after a time equivalent to 7 half-lives
N(t) = No•2^(-t / t½)
N(t) / No = 2^(-t / t½)
N(t) / No = 2^-7
N(t) / No = 7.81 × 10^-3
To percentage
N(t) / No = 7.81 × 10^-3 × 100
N(t) / No = 0.781 %
Density = (mass) / (volume)
4,000 kg/m³ = (mass) / (0.09 m³)
Multiply each side
by 0.09 m³ : (4,000 kg/m³) x (0.09 m³) = mass
mass = 360 kg .
Force of gravity = (mass) x (acceleration of gravity)
= (360 kg) x (9.8 m/s²)
= (360 x 9.8) kg-m/s²
= 3,528 newtons .
That's the force of gravity on this block, and it doesn't matter
what else is around it. It could be in a box on the shelf or at
the bottom of a swimming pool . . . it's weight is 3,528 newtons
(about 793.7 pounds).
Now, it won't seem that heavy when it's in the water, because
there's another force acting on it in the upward direction, against
gravity. That's the buoyant force due to the displaced water.
The block is displacing 0.09 m³ of water. Water has 1,000 kg of
mass in a m³, so the block displaces 90 kg of water. The weight
of that water is (90) x (9.8) = 882 newtons (about 198.4 pounds),
and that force tries to hold the block up, against gravity.
So while it's in the water, the block seems to weigh
(3,528 - 882) = 2,646 newtons (about 595.2 pounds) .
But again ... it's not correct to call that the "force of gravity acting
on the block in water". The force of gravity doesn't change, but
there's another force, working against gravity, in the water.