Answer:
Explanation:
1)Solution,
Distance(s)=30m
Time taken(t)=11s
Now,
Average velocity=s/t=30m/11s=2.72m/s
2)Solution,
Distance(s)=20km=20x1000m=20000m
Time(t)=9:30-8:30=1:30=60+30 min=90min=90x60=5400s
Now,
Average velocity=s/t=20000m/5400s=3.7m/s
v = √ { 2*(KE) ] / m } ;
Now, plug in the known values for "KE" ["kinetic energy"] and "m" ["mass"] ;
and solve for "v".
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Explanation:
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The formula is: KE = (½) * (m) * (v²) ;
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"Kinetic energy" = (½) * (mass) * (velocity , "squared")
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Note: Velocity is similar to speed, in that velocity means "speed and direction"; however, if you "square" a negative number, you will get a "positive"; since: a "negative" multiplied by a "negative" equals a "positive".
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So, we have the formula:
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KE = (½) * (m) * (v²) ; to solve for "(v)" ; velocity, which is very similar to the "speed";
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we arrange the formula ;
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(KE) = (½) * (m) * (v²) ; ↔ (½)*(m)* (v²) = (KE) ;
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→ We have: (½)*(m)* (v²) = (KE) ; we isolate, "m" (mass) on one side of the equation:
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→ We divide each side of the equation by: "[(½)* (m)]" ;
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→ [ (½)*(m)*(v²) ] / [(½)* (m)] = (KE) / [(½)* (m)]<span> ;
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to get:
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→ v² = (KE) / [(½)* (m)]
→ v² = 2 KE / m
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Take the "square root" of each side of the equation ;
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→ √ (v²) = √ { 2*(KE) ] / m }
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→ v = √ { 2*(KE) ] / m } ;
Now, plug in the known values for "KE" ["kinetic energy"] and "m" ["mass"];
and solve for "v".
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Answer:
10 °C
Explanation:
Applying
q = cm(t₂-t₁)............... Equation 2
Where q = heat energy, c = specific heat of ethanol, m = mass of ethanol, t₁ = initial temperature, t₂ = Final temperature.
Given: c = 2.44 J/g.°C, m = 300 g, q = 14640 J, t₂ = 30°C
Substitute into equation 2 and solve for t₁
14640 = 2.44×300(30-t₁)
14640 = 732(30-t₁)
732(30-t₁) = 14640
(30-t₁) = 14640/732
(30-t₁) = 20
t₁ = 30-20
t₁ = 10 °C
<span>The "scientific method" consists of forming a hypothesis (a statement about what the researchers think is true), collecting data that might confirm or refute the hypothesis, and then examining the data to see how well or poorly they support the original hypothesis.</span>
Waves transfer energy not matter. so simply put, the water doesn't move. it's just being used as a road that energy uses to get from point a to b. it's easier to think of some thing on the water rather than the water it self. like a cork floating on the surface. when a wave passes through the cork. the cork goes up to the peak of the wave and then down to the trough of the wave and then back at equilibrium. it only moved up and down since it was following the wave pattern. if the waves transfered matter as well as energy then the cork would begin to get pushed by the wave and move towards the direction of travel
