Answer:
a) y = 400 ft b) y = 350 ft
Explanation:
We can solve that problem with kinematic relationships
y = v₀ t + ½ a t²
Let's apply this equation to the elevator 1
y₁ = v₀ t₁ + ½ to t₁²
time t= 1 s
y₁ = v₀ 1 + ½ a 1²
y₁ = v₀ + ½ a
For t = 2s
y₂ = v₀ 2 + ½ a 2²
y₂ = 2 v₀ + 2 a
Let's write the equations and solve the system
4 = v₀ + ½ a
9 = 2 v₀ + 2 a
Let's multiply the first by -2
-8 = -2v₀ -a
9 = 2v₀ + 2 a
Let's add
1 = a
We replace in the first
4 = v₀ + ½ 1
v₀ = 4- 1/2
v₀ = 3.5
The equation for the first elevator is
y = 3.5 t + ½ t²
For t = 10 s
y = 3.5 10 + ½ 10²
y = 400 ft
We repeat the process for the second elevator
t = 1s
y₁ = v₀ 1 + ½ a 1²
3.5 = v₀ + ½ a
t = 2 s
y₂ = v₀ 2 + ½ a 2²
6.5 = 2 v₀ +2 a
multiply by -2
-7 = -2 v₀ - a
6.5 = 2 v₀ + 2 a
Let's add
-0.5 = a
I replace in the first equation
3.5 = v₀ + ½ (-0.5)
v₀ = 3.5 + 0.25
v₀ = 3.75
The equation is
y = 3.75 t -0.25 t²
For t = 10s
y = 3.75 10 - 0.25 10²
y = 350 ft
Answer:
Option 2. It cuts through all the other layers
Explanation:
Newer or younger rocks are usually formed from older rocks in the sense that older rocks are broken up, and their by product materials forming together to make younger rocks.
We can simply say that older rocks basically undergo recycling to form newer rocks.
Thus, looking at the given options,
For option 1, the newer rock cannot be crumpled while the others lie flat because it is the old one that is undergoing recycling and therefore the older one is the one that will be crumpled to give way for newer rocks. So it's not true.
For option 2, since they are from older rocks, they will clearly cut through the other layers of the old one because the old one will give way for the new one.
Option 3 is not true for the same reason given for option 1.
Option 4 is not true because there is no standard way in which it will be positioned
Answer:
The correct answer is = 1.6
Explanation:
Density of water = 1000kg/m³ = d₁
Mass of brick = 4kg = m
Density of brick = 2.5 g/cm³ = 2.5 × 1000 =2500 kg/m³ = d₂
Volume of brick = m/d₂ = 4/2500 =16/10000 = 0.0016 L = v
Buoyant Force = v × d₁ × g (g= acceleration due to gravity =9.8m/s²)
= 0.0016 × 1000 × 9.8 = 15.68 Newtons
By the Archimedes' Principle, the buoyant force is equal to the weight of the liquid displaced by an object.
Weight of the water displaced=Buoyant Force
=Mass of water displaced × g,
as weight = mass × acceleration due to gravity
15.68= mass of brick × 9.8
15.68/9.8 =Mass of water displaced
1.6 kg = Mass of water displaced
Potassium is in the most reactive group of elements, the alkali metals, but it's not the most reactive metal within the group. The alkali metals, Group 1A, are the most reactive metals because they have one valence or outer electron. They lose this electron very easily, forming ions with a charge of +1.
