8.0 m/s if there is no air resistance. (B)
Less if there IS any air resistance.
Answer:
0.67 s
Explanation:
This is a simple harmonic motion (SHM).
The displacement, 
, of an SHM is given by
A is the amplitude and 
is the angular frequency.
We could use a sine function, in which case we will include a phase angle, to indicate that the oscillation began from a non-equilibrium point. We are using the cosine function for this particular case because the oscillation began from an extreme end, which is one-quarter of a single oscillation, when measured from the equilibrium point. One-quarter of an oscillation corresponds to a phase angle of 90° or 
radian.
From trigonometry, 
if A and B are complementary.
At 
, 
So
At 
, 
The period, 
, is related to by
<span>The unknown substance is silver.
I don't see a list of available substances, but let's see if there's something reasonable available that will match. First, let's calculate the density of the unknown substance. Density is mass per volume, so
273 g / 26 mL = 10.5 g/mL
Looking up a list of elements sorted by density, I see the following:
10.07 Actinium
10.22 Molybdenum
10.5 Silver
11.35 Lead
And silver at 10.5 g/ml is a very nice match for the unknown substances' density of 10.5 g/ml.</span>
Explanation:
A pilot flying a weight; it takes t = 3.4 s to hit the ground, during which it travels a horizontal distance d = 120 m
h = g/2*t^2
h= 4.903*3.4^2
h=56.701 m
V = d/t
V= 120/3.4
V=35.3 m/sec
Now the pilot does a run at the same height but twice the speed.
How much time (t1) does it take the weight to hit the ground?
t1 = t = 3.4 sec (depending just upon height)
Transmit energy
Doesn’t transmit matter
