Answer:
t=4.86s
Explanation:
To find the wavelength you use the following formula:
v: speed of sound = 343m/s
f: frequency = 400Hz
λ: wavelength of the sound
By doing λ the subject of the formula and replacing the values of f and v you obtain:
Now, to calculate the time that sound takes to reach the last row you use:
t: time
d: distance to the last row = 1947m
hence, the time is 4.86s
Answer:
a. by moving the book without acceleration and keeping the height of the book constant
Explanation:
FOR CONSTANT KINETIC ENERGY:
The kinetic energy of a body depends upon its speed according to its formula:
ΔK.E = (1/2)mΔv²
So, for Δv = 0 m/s
ΔK.E = 0 J
So, for keeping kinetic energy constant, the books must be moved at constant speed without acceleration.
FOR CONSTANT POTENTIAL ENERGY:
The potential energy of a body depends upon its height according to its formula:
ΔP.E = mgΔh
So, for Δh = 0 m/s
ΔP.E = 0 J
So, for keeping potential energy constant, the books must be moved at constant height.
So, the correct option is:
<u>a. by moving the book without acceleration and keeping the height of the book constant</u>
M= Height of image/height of the object
If, M>1, then height of image>height of object.
And therefore, image is larger than the object.
Not having clean water to drink or bath. Also some organizations that live in the water might die because the water is polluted and that would be toxic form them
Answer:
60.2 J
Explanation:
Efficiency is the ratio of work out to work in.
e = Wout / Win
0.86 = Wout / 70 J
Wout = 60.2 J
