Answer:
We know that the second equation of motion is
S= ut + 1/2a²
And S is displacement and u is initial velocity
So in the case of Haley lets take downwards as positive Y-axis
S = 2h and
initial velocity = v
a = g (acceleration due to gravity = 9.8)
Substituting
2h = vt + 1/2gt²
And for Joe we take ownwards as positive Y-axis
S = h and
initial velocity = 0 (since the ball is dropped from rest)
a = g
h = 0x t + 1/2gt2²
t2= √ 2h/g
Now since both balls reach ground at same time: t1=t2
So
putting value of t2 in Hayley's equation:
2h= v(√2h/g) + 1/2 g( √2h/g)²
So v= √gh/2
High melting and boiling point
ionic bonds are very strong
a lot of energy is needed to break them
conductive when liquid
ionic com. can only conduct electricity if their ions are free to move
Answer:
The amount of kilograms of ice at -20.0°C that must be dropped into the water to make the final temperature of the system 40.0°C = 0.0674 kg
Explanation:
Heat gained by ice in taking the total temperature to 40°C = Heat lost by the water
Total Heat gained by ice = Heat used by ice to move from -20°C to 0°C + Heat used to melt at 0°C + Heat used to reach 40°C from 0°C
To do this, we require the specific heat capacity of ice, latent heat of ice and the specific heat capacity of water. All will be obtained from literature.
Specific heat capacity of ice = Cᵢ = 2108 J/kg.°C
Latent heat of ice = L = 334000 J/kg
Specific heat capacity of water = C = 4186 J/kg.°C
Heat gained by ice in taking the total temperature to 40°C = mCᵢ ΔT + mL + mC ΔT = m(2108)(0 - (-20)) + m(334000) + m(4186)(40 - 0) = 42160m + 334000m + 167440m = 543600 m
Heat lost by water = mC ΔT = 0.25 (4186)(75 - 40) = 36627.5 J
543600 m = 36627.5
m = 0.0674 kg = 67.4 g of ice.
Answer:
Explanation:
If we express all of the cordinates in their rectangular form we get:
A = (1404.77 , 655.06) m
Since we need C to be (0,0) we stablish that:
That way we make an equation system from both X and Y coordinates:
Replacing values:
With this system we can solve for both Db and Dc and get the answers to the question: