<span>The correct answer is option B. i.e.invention of the microscope. Galileo Galilei invented the microscope and showed its use. Sir Issac Newton invented some part of the calculus, Also invented Newton's Laws of motion and the universal gravitation theory.</span>
We assume that horn releases sound of constant frequency. In order for observer to observe different frequency either horn or observer or both must move.
This happens due to Doppler effect. It states that when position of source of sound and observer relative to each other changes, the observed frequency also changes. If the source emits sound of constant frequency than observed frequency will be either higher or lower than original.
When distance between source and observer increases the observed frequency will be lower. This is because same number of sound waves must cover greater distance so they have greater wavelength.
When distance between source and observer decreases the observed frequency will be higher. This is because same number of sound waves must cover smaller distance so they have smaller wavelength.
Wavelength and frequency are inversely proportional meaning when one increases the other drecreases.
From this explanation we can find answer for our question. <span>If we wanted the pitch of a horn to drop relative to an observer we need to move horn away from an observer.</span>
Answer:
<em><u>5</u></em><em><u>0</u></em><em><u>.</u></em><em><u>6</u></em><em><u>3</u></em><em><u> </u></em><em><u>f</u></em><em><u>t</u></em><em><u>/</u></em><em><u>s</u></em><em><u> </u></em><em><u>(</u></em><em><u>2</u></em><em><u>d</u></em><em><u>p</u></em><em><u>)</u></em>
Explanation:
Speed = Distance/Time
80/1.58 = 50.63291139
= <u>50.63</u><u> </u><u>f</u><u>t</u><u>/</u><u>s</u> (2dp)
Answer: Smoke is Abiotic because it is not a living thing.
Explanation: Hopefully this helps u. Have a great rest of your day. I hope this is the right answer
Answer:
option (c) is correct
Explanation:
Half life of a substance is the time in which the element becomes half of is initial value.
half life, T = 8 days
Amount remaining, N = 10 % of original value
Let the original value is No.
N = 10% of No
N = 0.1 No
Let the time taken is t and the decay constant is λ.
The relation between the decay constant and the half life is given by

Us the equation of radioactivity



Taking natural log on both the sides, we get
0.08664 t = 2.303
t = 26.6 days