The relevant formula we can use in this case would be:
h = v0 t + 0.5 g t^2
where,
h = height or distance travelled
v0 = initial velocity = 0 since it was dropped
t = time = 1 seconds
g = 9.8 m/s^2
So calculating for height h:
h = 0 + 0.5 * 9.8 m/s^2 * (1 s)^2
<span>h = 4.9 meters</span>
Let
V the speed of the girl per step
v the speed of the escalator per step
L the length between ground and floor in number of steps
V*60+v*60=L => V+v=L/60
V*90-v*90=L => V-v=L/90
By adding the equations V+v=L/60 and V-v=L/90 we get:
2V=L(3+2)/180
V=5L/360
V = L/72
Time to climb (in steps) with v=0 (escalator standing still) is:
V*t=L
t = L/V
t = L/(L/72)
t =72 steps
The girl will count 72 steps.
By converting the 400 nm wavelength of violet light into meters we are get 4.0.10^-7.
What is wavelength?
Wavelength can be defined as the distance between two successive crests or throughs of a wave. It is measured in the direction of the wave. The wavelength of light defined as the distance between the two successive crests or throughs of the light wave.The wavelength of light is the distance between corresponding point in two adjacent light cycles and the frequency.
To know more about wavelength click -
brainly.com/question/10750459
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Explanation:
Given that,
Two resistors 4.5 Ω and 2.3 Ω .
Potential difference = 30 V
When they are in series, the current through each resistor remains the same. First find the equivalent resistance.
R' = 4.5 + 2.3
= 6.8 Ω
Current,
So, the current through both lightbulb is the same i.e. 4.41 A.
When they are in parallel, the current divides.
Current flowing in 4.5 resistor,
Current flowing in 2.3 ohm resistor,
In parallel combination, are brighter than bulbs in series.
It is A: They add energy to the work
