There are NO true statements on the list you provided.
Answer:
dJ = 1.7 m
Explanation:
The Equation of the Balancing the moments in the center of the seesaw is like this:
∑Mo = 0
Mo = F*d
Where:
∑Mo : Algebraic sum of moments in the center(o) of the balance
Mo : moment in the o point ( N*m)
F : Force ( N)
d : distancia of the force to the the o point ( N*m)
Data
mA = 60 kg : mass of the Anna
mJ = 70 kg : mass of theJon
dA = 2 m : Distance from Anna to the center of the seesaw
g: acceleration due to gravity
Calculation of the distance from Jon to the center of the seesaw (dJ)
∑Mo = 0 WA : Ana's weight , WJ : Jon's weight
W = m*g
(WA)(dA) - (WJ) (dJ) = 0
(mA*g)(dA) - (mJ*g)(dJ) = 0
We divide by g the equation:
(mA)(dA) - (mJ)(dJ)= 0
(mA)(dA) = (mJ)(dJ)


dJ = 1.7 m
No they are not the same material because having the same density doesnt mean its the same material also they can have a different density and be the same material
Answer:
7.6 g
Explanation:
"Well lagged" means insulated, so there's no heat transfer between the calorimeter and the surroundings.
The heat gained by the copper, water, and ice = the heat lost by the steam
Heat gained by the copper:
q = mCΔT
q = (120 g) (0.40 J/g/K) (40°C − 0°C)
q = 1920 J
Heat gained by the water:
q = mCΔT
q = (70 g) (4.2 J/g/K) (40°C − 0°C)
q = 11760 J
Heat gained by the ice:
q = mL + mCΔT
q = (10 g) (320 J/g) + (10 g) (4.2 J/g/K) (40°C − 0°C)
q = 4880 J
Heat lost by the steam:
q = mL + mCΔT
q = m (2200 J/g) + m (4.2 J/g/K) (100°C − 40°C)
q = 2452 J/g m
Plugging the values into the equation:
1920 J + 11760 J + 4880 J = 2452 J/g m
18560 J = 2452 J/g m
m = 7.6 g