The answer is C. <span>Light travels at different speeds in water and in glass.</span>
D, 0.140 liters! Hang on a sec and I'll show you a trick I use.
Wavelength of X-rays = 10⁻¹⁰ m
Wavelength of UV = 1000 x 10⁻¹⁰
= 10⁻⁷ m
Gravity adds 9.8 m/s to the speed of a falling object every second.
An object dropped from 'rest' (v = 0) reaches the speed of 78.4 m/s after falling for (78.4 / 9.8) = <em>8.0 seconds</em> .
<u>Note:</u>
In order to test this, you'd have to drop the object from a really high cell- tower, building, or helicopter. After falling for 8 seconds and reaching a speed of 78.4 m/s, it has fallen 313.6 meters (1,029 feet) straight down.
The flat roof of the Aon Center . . . the 3rd highest building in Chicago, where I used to work when it was the Amoco Corporation Building . . . is 1,076 feet above the street.
Answer:
Explanation:
Remark
At the time it takes to drop 20 m is the same time it takes to travel 60 m horizontally.
Givens
h = 20 m
hd = 60 m
g = 9.81
vi = 0
Formula
d = vi*t + 1/2 a * t^2 We are solving for t
Solution
When the battery fails, the vertical initial velocity is 0. So we have to find the time it would take to drop 20 meters
d = 0*t + 1/2 * 9.81 a* t^2
20 = 4.91 * t^2 Divide by 4.91
20/4.91 = 4.91 t^2 / 4.91
4.073 = t^2 Take the square root of both sides.
t = 2.02 seconds
Horizontal
d = 60 m
t = 2.02 seconds
v = ?
Note: there is no horizontal deceleration or acceleration
v = d/t
v = 60/2.02
Answer: v = 29.73 m/s