A positive acceleration indicates that the object sped up. This means that if you compare the first speed to the second, the second speed should be higher.
A negative acceleration indicates that the object has slowed down. This means that if you compare the first speed to the second, the second speed should be lower.
If an acceleration is 0, it means that it neither slowed down nor sped up.
Now let us analyze your problem by listing down the speed and the time:
At noon: 4 mi/hr
12:30 : 6 mi/hr
2:30 : 2 mi/hr
From noon to 12:30, you will notice that there is an increase in speed. This means that Tommy had a positive acceleration. (Rules out D.)
From 12:30 to 2:30, there is a decrease in speed. This would indicate that Tommy had a negative acceleration. (Rules out C.)
No speed was the same, so acceleration was never 0. (Rules out A.)
From the assumptions above, we can now deduce that the answer is B.
Butterflies are cold-blooded and need the light from the sun to warm the muscles they use to fly. Not only do butterflies like the sun, the plants the they thrive on need full direct sun. Most plants need at least 8 hours of sunlight to bloom properly and provide enough nectar.
Answer:
P₂ = 0.09 atm
Explanation:
According to general gas equation:
P₁V₁/T₁ = P₂V₂/T₂
Given data:
Initial volume = 0.225 L
Initial pressure = 338 mmHg (338/760 =0.445 atm)
Initial temperature = 72 °C (72 +273 = 345 K)
Final temperature = -15°C (-15+273 = 258 K)
Final volume = 1.50 L
Final pressure = ?
Solution:
P₁V₁/T₁ = P₂V₂/T₂
P₂ = P₁V₁ T₂/ T₁ V₂
P₂ = 0.445 atm × 0.225 L × 258 K / 345 K × 1.50 L
P₂ = 25.83 atm .L. K / 293 K . L
P₂ = 0.09 atm
Explanation:
The four nitrogenous bases present in DNA are adenine (A), guanine (G), cytosine (C) and thymine (T).
1. The reaction for this would be:
Sn + 4 HNO₃ → SnO₂ + 4 NO₂ + 2 H₂O
The first observation would be bubbling of the solution and brown acrid smoke is produced due to the presence of NO₂ gas. Another observation would be the presence of a white solid which is SnO₂.
2. Heating was required to get rid of the H₂O. When all moisture is gone, you weigh the sample. Afterwhich, you further heat it to get ride of the oxygen. By doing this, you would know the individual mass of each element. Then, you can solve for the empirical formula of the oxide of tin.