Answer:
B) 2.7 g of aluminium has a volume of 1 cm^3
Explanation:
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the equation;
![Density = \frac{mass}{volume}](https://tex.z-dn.net/?f=Density%20%3D%20%5Cfrac%7Bmass%7D%7Bvolume%7D)
If the density of aluminum is 2.7 g/cm³, it simply means that 2.7 g of aluminium has a volume of 1 cm³
Check:
Given the following data;
Mass = 2.7 grams
Volume = 1 cm³
Substituting into the formula, we have;
![Density = \frac{2.7}{1}](https://tex.z-dn.net/?f=Density%20%3D%20%5Cfrac%7B2.7%7D%7B1%7D)
Density = 2.7 g/cm³
Answer:
The answer to your question is: 15 pizzas
Explanation:
data
26 large pizzas ------ 66 students
? large pizzas -------- 38 students
Rule of three
x = 38 (26) / 66 = 14.96 ≈ 15 pizzas
Can you get a better pic so i can read it
Answer:
Explanation:
Let the velocity be v
Total energy at the bottom
= rotational + linear kinetic energy
= 1/2 Iω² + 1/2 mv² ( I moment of inertia of shell = mr² )
= 1/2 mr²ω² + 1/2 mv² ( v = ω r )
= 1/2 mv² +1/2 mv²
= mv²
mv² = mgh ( conservation of energy )
v² = gh
v = √gh
= √9.8 x 1.8
= 4.2 m /s
Answer:
D. 130 J
Explanation:
The coefficient of performance for a machine that is being used to cool, is given by:
![COP=\frac{Q_C}{W}=\frac{T_C}{T_H-T_C}](https://tex.z-dn.net/?f=COP%3D%5Cfrac%7BQ_C%7D%7BW%7D%3D%5Cfrac%7BT_C%7D%7BT_H-T_C%7D)
Here
is the heat removed from the cold reservoir, W is the work required, that is, the energy required to remove the heat from the interior of the house,
is the cold temperature and
is the hot temperature. Recall use absolutes temperatures(
). Replacing and solving for W:
![W=Q_c\frac{T_H-T_C}{T_C}\\W=2000J\frac{312.15K-293.15K}{293.15K}\\W=129.63J](https://tex.z-dn.net/?f=W%3DQ_c%5Cfrac%7BT_H-T_C%7D%7BT_C%7D%5C%5CW%3D2000J%5Cfrac%7B312.15K-293.15K%7D%7B293.15K%7D%5C%5CW%3D129.63J)