From the diagram we have that
Therefore the direction is 30° from east of south
<span>22.5 newtons.
First, let's determine how much energy the stone had at the moment of impact. Kinetic energy is expressed as:
E = 0.5mv^2
where
E = Energy
m = mass
v = velocity
Substituting known values and solving gives:
E = 0.5 3.06 kg (7 m/s)^2
E = 1.53 kg 49 m^2/s^2
E = 74.97 kg*m^2/s^2
Now ignoring air resistance, how much energy should the rock have had?
We have a 3.06 kg moving over a distance of 10.0 m under a force of 9.8 m/s^2. So
3.06 kg * 10.0 m * 9.8 m/s^2 = 299.88 kg*m^2/s^2
So without air friction, we would have had 299.88 Joules of energy, but due to air friction we only have 74.97 Joules. The loss of energy is
299.88 J - 74.97 J = 224.91 J
So we can claim that 224.91 Joules of work was performed over a distance of 10 meters. So let's do the division.
224.91 J / 10 m
= 224.91 kg*m^2/s^2 / 10 m
= 22.491 kg*m/s^2
= 22.491 N
Rounding to 3 significant figures gives an average force of 22.5 newtons.</span>
Answer:
<h2>230476.19km</h2>
Explanation:
Step one:
given
Force F= 210N
mass m= 1600kg
velocity v=5500m/s
Step two
Required is the radius r
the expression for the force is
substitute
210=1600*5500^2/r
cross multiply we have
210r=48400000000
divide both side by 210
r=230476190.476m
r=230476.19km
<span>Ok, you need to derive it.
Derive v^2</span>
In order to solve problems like this, you need to know that whenever
there are waves involved ...
<u>(wavelength) x (frequency) = speed of the wave </u>.
Both of these problems are about sound, so you'll need to know the speed
of sound. I'm going to use 340 meters per second. You should look it up to
see if that's a reasonable number.
1). (wavelength) x (frequency) = speed of the wave
The wavelength is given, and I picked a number for the speed.
(0.667 m) x (frequency) = (340 m/s)
Divide each side by 0.667 m : Frequency = (340 m/s) / (0.667 m) = <em>509.7 Hz</em>.
2). I picked a number for speed, and two frequencies are given.
We have to find the wavelength for each frequency.
<u>20 Hz:</u>
(wavelength) x (frequency) = speed of the wave
(wavelength) x (20 Hz) = 340 m/s
Divide each side by 20 Hz: Wavelength = (340 m/s) / (20 Hz) = <em>17 m</em>
<u>16,000 Hz:</u>
(wavelength) x (frequency) = speed of the wave
(wavelength) x (16,000 Hz) = 340 m/s
Divide each side by 16,000 Hz: Wavelength = (340 m/s)/(16,000 Hz) = <em>2.125 cm </em>
I also want to tell you how much I like the wavy appearance of these
questions about waves in the picture you attached !
