Answer:
The car must be moving away from the person.
Explanation:
From Doppler's Effect, we know that when a sound source moves towards a stationary observer, the apparent frequency of that sound increases. While the apparent frequency decreases if the source moves away from the stationary observer.
The audible range of frequencies for a human ear is 20 Hz to 20000 Hz. Therefore, in order for the sound of a loud speaker to be audible for the person, the frequency must decrease below 20000 Hz.
<u>Due to this reason, the car must be moving away from the person.</u>
Answer:
D. the masses of the objects and the distance between them
Explanation:
Gravitation is a force, a force doesn't care about the shape or density of objects, only about their masses... and distances.
And you can get it using the following equation:

Where :
G is the universal gravitational constant
: G = 6.6726 x 10-11N-m2/kg2
m represent the mass of each of the two objects
d is the distance between the centers of the objects.
Answer:
I. a, c, f and h
II. e
III. b, d, g and i
IV. i
Explanation:
I. Chemical symbols are simple abbreviations used to represent various elements or compound. They consist entire of alphabet.
For the diagram given above, the labelled parts which represent chemical symbol are: a, c, f and h
II. Coefficients are numbers written before the chemical symbol of elements or compound.
For the diagram given above, the labelled part which represent Coefficient is: e
III. Number of atoms of element present in a compound is simply obtained by taking note of the numbers written as subscript in the chemical formula of the compound.
For the diagram given above, the labelled part which represent the number of atoms of the element are: b, d, g and i
IV. When no number is written as subscript in the formula of the element in the compound, it means the element has just 1 atom in the compound.
For the diagram given above, the labelled part which indicates that only 1 atom of the element is present is: i
Answer:
sorry in my sense, an experiment once only changes one variable and need a control setup for experimental setup to make sure is fair test
Answer:
Workdone = 20 Joules
Explanation:
Given the following data;
Force = 10N
Extension, e = 4cm to meters = 4/100 = 0.04 meters
Workdone extension = 40cm to meters = 40/100 = 0.4 meters
To find the work done;
First of all, we would find the spring constant using the formula;
Force = spring constant * extension
10 = spring constant * 0.04
Spring constant = 10/0.04
Spring constant = 250 N/m
Next, we find the work done;
Workdone = ½ke²
Where;
k is the spring constant.
e is the extension.
Substituting into the formula, we have;
Workdone = ½ * 250 * 0.4²
Workdone = 125 * 0.16
Workdone = 20 Joules