You could answer this right away IF you knew the length of each wave, right ?
Well, Wavelength = (speed) / (frequency).
Speed = 3 x 10⁸ m/s (the speed of light)
and
Frequency = 90.9 x 10⁶ Hertz.
So the length of each wave is 3 x 10⁸ / 90.9 x 10⁶ meters.
To answer the question, see how many pieces you have to cut
that 1.5 km into, in order for each piece to be 1 wavelength.
It'll be
(1,500 meters) divided by (3 x 10⁸ meters/sec) / (90.9 x 10⁶ Hz)
To divide by a fraction, flip the fraction and then multiply:
(1500 meters) times (90.9 x 10⁶ Hz)/(3 x 10⁸ meters/sec)
= 454.5
Answer:
At 2km/h*s it is changing speed every 2 seconds.
At 4km/h*s it is changing speed every 4 seconds.
At 10km/h*s it is changing speed every 10 seconds.
The total momentum of the system is preserved through the collision.
Note that momentum is
P = m*v
where m = mass
v = velocity.
Initial momentum:
P1 = (30000 kg)*(2 m/s) = 60000 (kg-m)/s for the moving car
P2 = 0 for the starionary car.
Final momentum:
P3 = (30000 + 30000)*v = 60000v (kg-m)/s
Because momentum is preserved,
P3 = P1 + P2
60000v = 60000
v = 1 m/s
The final velocity is 1 m/s.
Answer: 1.0 m/s
Answer:
48 kmph
Explanation:
The question is asking you the kmph and that means the amount of kilometers travelled divided by the amount of hours. And if you want to think of it in a formula, SPEED = DISTANCE ÷ TIME
In this case, the amount of hours is 2.5 and the speed is 120km so 120/2.5 is 48
so the answer is 48 kmph
The photon energy is the light frequency times Planck's constant. ... Planck's constant is usually called "h". Its value is about 6.626*10^-34 Joules/ Hz. A Joule is a unit of energy, and a Hertz is a unit of frequency, so when you multiply a frequency by h you get an energy.