Answer:
0.001 s
Explanation:
The force applied on an object is equal to the rate of change of momentum of the object:

where
F is the force applied
is the change in momentum
is the time interval
The change in momentum can be written as

where
m is the mass
v is the final velocity
u is the initial velocity
So the original equation can be written as

In this problem:
m = 5 kg is the mass of the fist
u = 9 m/s is the initial velocity
v = 0 is the final velocity
F = -45,000 N is the force applied (negative because its direction is opposite to the motion)
Therefore, we can re-arrange the equation to solve for the time:

Recall that average velocity is equal to change in position over a given time interval,

so that the <em>x</em>-component of
is

and its <em>y</em>-component is

Solve for
and
, which are the <em>x</em>- and <em>y</em>-components of the copter's position vector after <em>t</em> = 1.60 s.


Note that I'm reading the given details as

so if any of these are incorrect, you should make the appropriate adjustments to the work above.
Answer:
f = 6.37 Hz, T = 0.157 s
Explanation:
The expression you have is
y = 5 sin (3x - 40t)
this is the equation of a traveling wave, the general form of the expression is
y = A sin (kx - wt)
where A is the amplitude of the motion, k the wave vector and w the angular velocity
Angle velocity and frequency are related
w = 2π f
f = w / 2π
from the equation w = 40 rad / s
f = 40 / 2π
f = 6.37 Hz
frequency and period are related
f = 1 / T
T = 1 / f
T = 1 / 6.37
T = 0.157 s
Infrared radiation<span> lies between the </span>visible<span> and microwave portions of the electromagnetic spectrum. Infrared waves have wavelengths longer </span>than visible<span> and shorter </span>than<span> microwaves, and have </span>frequencies<span> which are lower </span>than visible<span> and </span>higher than<span> microwaves.</span>