Answer:
The mass of the Al-duckie should be 30 kg.
Explanation:
We will use the first law of thermodynamics:
ΔU = m·Cv·ΔT
Since the specific heat of water is 4.185 J(gºC), the change in the water's internal energy would be:
ΔU = 100 kg · 4.185 J(gºC) · (42ºC - 38ºC) = 1674 KJ
Given that no heat is lost, all the internal energy that the water loses while cooling down will transfer to the duckie. So, if the duckie has ΔU = 1674 KJ and its final temperature is the desired 38 ºC, we can calculate its mass using the first law again:
![m=\frac{\Delta{U}}{Cv{\Delta{T}}}=\frac{1674}{0.9*[38-(-24)]}=30Kg](https://tex.z-dn.net/?f=m%3D%5Cfrac%7B%5CDelta%7BU%7D%7D%7BCv%7B%5CDelta%7BT%7D%7D%7D%3D%5Cfrac%7B1674%7D%7B0.9%2A%5B38-%28-24%29%5D%7D%3D30Kg)
Answer:
I think, (remember think) it might be 2.0 m/s
Explanation:
If it's wrong I'm truly sorry.
The answer is a because tjhey do move at a molecular movemn
Answer:
85 miles .
Explanation:
Displacement along the 110 South freeway = 260 - 150 = 110 miles
Displacement along the 110 North freeway = 150 - 175 = - 25 miles
Net displacement = 110 - 25 = 85 miles
So Joey's displacement from the 260 mile marker is 85 miles .