100m ÷ 50s = 2m/s
Just some simple divison.
The answer is C. ionic compounds, compared to another hard compound which is the covalent bond, the structure of the ionic compound is lattice or crystalline in form thus less room for imperfections on its structure compared to the latter choices.
Answer:
Suppose the micrometeoroid weighed 1 g = .001 kg
Suppose also the spacecraft were moving at 18,000 mph (1.5 hrs per rev)
Usually, the smaller particle would be moving but for simplicity suppose that it were stationary wrt the ground
v = 18000 miles / hr * 1500 m/mile / 3600 sec/hr = 7500 m/s
KE = 1/2 * .001 kg * (7500 m)^2 = 28,125 Joules
One can see that 28000 Joules could be damaging amount of energy
I'll bite:
-- Since the sled's mass is 'm', its weight is 'mg'.
-- Since the coefficient of kinetic friction is μk, the force acting opposite to the direction it's sliding is (μk) times (mg) .
-- If the pulling force is constant 'F', then the horizontal forces on the sled
are 'F' forward and (μk · mg) backwards.
-- The net force on the sled is (F - μk·mg).
(I regret the visual appearance that's beginning to emerge,
but let's forge onward.)
-- The sled's horizontal acceleration is (net force) / (mass) = (F - μk·mg) / m.
This could be simplified, but let's not just yet.
-- Starting from rest, the sled moves a distance 's' during time 't'.
We know that s = 1/2 a t² , and we know what 'a' is. So we can write
s = (1/2 t²) (F - μk·mg) / m .
Now we have the distance, and the constant force.
The total work is (Force x distance), and the power is (Work / time).
Let's put it together and see how ugly it becomes. Maybe THEN
it can be simplified.
Work = (Force x distance) = F x (1/2 t²) (F - μk·mg) / m
Power = (Work / time) = <em>F (t/2) (F - μk·mg) / m </em>
Unless I can come up with something a lot simpler, that's the answer.
To simplify and beautify, make the partial fractions out of the
2nd parentheses:
<em> F (t/2) (F/m - μk·m)</em>
I think that's about as far as you can go. I tried some other presentations,
and didn't find anything that's much simpler.
Five points,ehhh ?
Hi there!
According to Newton's second law:
∑F = m · a, where:
∑F = net force (N = kgm/s²)
m = mass (kg)
a = acceleration (m/s²)
Rearrange to solve for acceleration:
F/m = a
20N / 4.0kg = 5 m/s²
