The car travels a distance <em>d</em> from rest with acceleration <em>a</em> after time <em>t</em> of
<em>d</em> = 1/2 <em>a</em> <em>t</em>²
It covers 69 m with 2.8 m/s² acceleration, so that
69 m = 1/2 (2.8 m/s²) <em>t</em>²
<em>t</em>² = 2 (69 m) / (2.8 m/s²)
<em>t</em> ≈ 7.02 s
where we take the positive square root because we're talking about time *after* the car begins accelerating.
Answer:
Explanation:
Let the thickness of the film is t and the refractive index of the material of film is n.
When light travels through a sheet of thickness t, the optical path traveled is nt.
When the path of one of slit is covered by a sheet of thickness t, the optical path becomes
x = ( n - 1) t
As the one fringe is shift, so the optical path changed by one wavelength.
i.e., x = λ
So, λ = ( n - 1) t

The particles of the medium (slinky in this case) move up and down (choice #2) in a transverse wave scenario.
This is the defining characteristic of transverse waves, like particles on the surface of water while a wave travels on it, or like particles in a slack rope when someone sends a wave through by giving it a jolt.
The other kind of waves is longitudinal, where the particles of the medium move "left-and-right" along the direction of the wave propagation. In the case of the slinky, this would be achieved by giving a tensioned slinky an "inward" jolt. You would see that such a jolt would give rise to a longitudinal wave traveling along the length of the tensioned slinky. Another example of longitudinal waves are sound waves.
Answer:
-730KJ
Explanation:
According to the first law of thermodynamics;
Let the total energy of the system be ∆E
Let heat be q and let work the w
Since the energy decreases ∆E is negative
Since work is done on the system w= positive
So;
- 250 = 480 + q
q = -250 - 480
q=-730KJ