Answer:
t = 7,8 s
Explanation:
From the instant, the rabbit passes the cat. The cat star running acceleration of 0,5 m/s² .
When the cat arrives at the speed of 3,9 m/s the cat catches the rabbit
Then for the cat arrives at 3,9 m/s nedds
v = vo + a*t vo = 0 then v = a*t
3,9 ( m/s) = 0,5 ( m/s² ) * t
t = 7,8 s
v = 3,9 m/s =
Answer:
a = Δv/t = (vf - vi)/t = (0 - 5)/4 = -1.25 m/s²
Explanation:
You may or may not need the negative sign, depending on how the question designer was thinking about the problem.
<h2>The temperature of the air is 66.8° C</h2>
Explanation:
From the Newton's velocity of sound relationship , the velocity of sound is directly proportional to the square root of temperature .
In this case The velocity of sound = frequency x wavelength
= 798 x 0.48 = 383 m/sec
Suppose the temperature at this time = T K
Thus 383 ∝
I
The velocity of sound is 329 m/s at 273 K ( given )
Thus 329 ∝
II
Dividing I by II , we have
= 
or
= 1.25
and T = 339.8 K = 66.8° C
Planck's equation states that
E = hf
where
E = the energy,
h = Planck's constant
f = the frequency
Because
c = fλ
where
c = velocity of light,
λ = wavelength
therefore
E = h(c/λ)
Photon #1:
The wavelength is λ₁ = 60 nm.
The energy is
E₁ = (hc)/λ₁
Photon #2:
The energy is twice that of photon #1, therefore its energy is
E₂ = 2E₁ = (hc)/λ₂.
Therefore

Answer: 30 nm