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.
Answer:
5cm east& 1cm west from A
Explanation:
https://brainly.ph/question/2753392
Need more details to the question
Answer:
1) black body radiation
2) Electromagnetic radiation through the window
Explanation:
Blackbody radiation is the radiation produced by heated objects, particularly from a blackbody. The car is heated by sunshine. Actually, everything is heated by sunshine, and the car being a blackbody object absorbs all radiation (visible light, infrared light, ultraviolet light, etc.) that falls on it. This also means that it will also radiate at all frequencies that heat energy produces in it.
Radiation from the Sun is absorbed, through the glass, by the inside of the car. That is why it helps to have tinted glass or use a screen on the windows while it is parked.
Answer:
She needs 250 g more of potting soil.
Explanation:
Write 1 kg in grams, so you can compare the quantities in the same units: 1 kg = 1000 g
Then, since she has 750 g, she needs 1000 g - 750 g = 250 g to complete her task.
