We know, Potential Energy = m * g * h
Here, mass & gravity would be same, but their height will change so it will be:
ΔU = U₂ - U₁
ΔU = mgh₂ - mgh₁
ΔU = mg (h₂ - h₁)
Hope this helps!
Answer:
a. The magnitude of the tension in the string is greater than the magnitude of the weight of the rock.
Explanation:
During the motion of the rock while it is in downward motion we can say

since it is performing circular motion so we will have its acceleration towards its center



So at the lowest point of the path we can say

so correct answer is
a. The magnitude of the tension in the string is greater than the magnitude of the weight of the rock.
Answer:
48.7°C
Explanation:
Step one:
given data
Quantity of heat = 4000J
mass of sample= 70g= 0.07kg
initial temperature T1=35°C
Water has a specific heat capacity of 4182 J/kg°C
Required
The final temperature T2
Step two:
Q= mcΔT
4000= 0.07*4182(T2-35)
4000=292.74(T2-35)
4000=292.74T2-10245.9
collect like terms
4000+10245.9=292.74T2
14245.9= 292.74T2
divide both sides by 292.74
T2= 14245.9/ 292.74
T2=48.7°C