Heat will be transferred from iron to water, because heat flows always from the higher temperature system to the lower temperature system.
Because Helium fusion in a shell outside the core generates enough thermal pressure to push the upper layers outward.
Answer:
The precise point is that gravitational energy is potential energy unless it makes something move, and then the energy is converted to kinetic energy, no work can be done. So a big rock at the top of a hill has no kinetic energy. Its only when it rolls down that work is done, and this can be converted to useful energy.
Explanation:
Answer:
The minimum value is 
Explanation:
From the question we are given that
The voltage is 
The internal resistance is 
The objective of this solution is to obtain the minimum value of the voltmeter resistance for which the voltmeter reading is within 1.0% of the emf of the battery
What is means is that we need to obtain voltmeter resistance such that
V = (100% -1%) of E
Where E is the e.m.f of the battery and V is the voltmeter reading
i.e V = 99% of E = 0.99 E = 7.425
Generally
E = V + ir
where ir is the internal potential difference of the voltmeter and
V is the voltmeter reading
Making i the subject of the formula above



Now the current is constant through out the circuit so,

Where
is the value of voltmeter resistance
Hence 

False. Since the forces are pulling in equal and opposite directions, the net force is 0.