The gravitational force <em>F</em> between two masses <em>M</em> and <em>m</em> a distance <em>r</em> apart is
<em>F</em> = <em>G M m</em> / <em>r</em> ²
Decrease the distance by a factor of 7 by replacing <em>r</em> with <em>r</em> / 7, and decrease both masses by a factor of 8 by replacing <em>M</em> and <em>m</em> with <em>M</em> / 8 and <em>m</em> / 8, respectively. Then the new force <em>F*</em> is
<em>F*</em> = <em>G </em>(<em>M</em> / 8) (<em>m</em> / 8) / (<em>r</em> / 7)²
<em>F*</em> = (1/64 × <em>G M m</em>) / (1/49 × <em>r</em> ²)
<em>F*</em> = 49/64 × <em>G M m</em> / <em>r</em> ²
In other words, the new force is scaled down by a factor of 49/64 ≈ 0.7656, so the new force has magnitude approx. 76.56 N.
Answer:
Speed of sound is 30.91m/s
Explanation:
Speed is given by:
Speed = distance travelled / time taken
Given:
Distance travelled = 1020m
Time taken = 33seconds
Speed = 1020m/33s
Speed = 30.91m/s
Answer: The sound level of the singers is
86.96dB
Explanation:
sound wave can be described by the intensity of sound, which is measured in decibels. The actual intensity, in watts per square meter, varies over a very wide range, so the logarithmic scale is more convenient in intensity characterization. The intensity in decibels is given by 10log10 (I/Io)
Where Io= 10^-12W/m^2 is called the threshold of hearing.
If the intensity of sound produced by 1 singer is I the intensity of sound of 36 singers will be 36I
X = 10log10 (36I/ Io)
Transforming, we have,
X = 10log10 36 + 10log10(I/Io)
X = 10log10 36 + 71.4 fb
X = 15.56 + 71.4 fb
X = 86.96dB
<span>False, it is the other way around. Instead of
Axis powers were made up of a coalition of countries that opposed the Allied
powers in World War II, it is opposite. <span>World
War II was the effect of the remnants of conflicts after World War I
(1914-1918) and Adolf Hitler’s attack on Poland on September 1939 Great Britain
and France to declare war. World War II continued for 6 years being named as
the ‘deadliest war in the history’, involved thirty countries and an estimation
of eighty-five million deaths. The following are the involved countries during the
war:
Axis Powers: Germany, Italy, Japan
Co-signers of the Tripartite Treaty: Bulgaria, Hungary, Romania, Slovakia
Countries in conflict with Axis Powers( before the World War II): Austria,
Ethiopia, Republic of China Allied Powers: Australia, Brazil, Canada,
Newfoundland, New Zealand, South Africa, Soviet Union, United Kingdom, United
States
Supporters of the Allies: Dominican Republic, Ecuador, Bolivia, Chile,
Guatemala, Colombia , Cuba, Costa Rica, Egypt, El Salvador, Haiti, Honduras, Iraq,
Lebanon, Liberia, Mexico, Mongolia, Nicaragua, Panama, Paraguay, Argentina,
Peru, Saudi Arabia, Turkey, Uruguay, Venezuela
Countries that were attacked: Norway, Philippines, Algeria, Thailand,
Tunisia, Yugoslavia Albania, Belgium, Latvia, Lithuania, Burma, Czechoslovakia,
Denmark, Estonia, Finland, France, Luxembourg, Morocco, Netherlands, Greece,
Iceland, India, Iran, Poland, Singapore, Syria,</span></span>