Answer:
(A) Q = 2.26×10⁶J
(B) ΔT = 9°C
(C)
Explanation:
We have been given the mass of the hiker, the volume of water from which we can calculate the mass knowing that the density if water is 1000kg/m³.
Evaporation is a phase change and occurs at a constant temperature. We would use the latent heat of vaporization to calculate the amount of heat evaporated.
We would then equate this to the heat change it brings about in the hiker's body and then calculate the temperature drop.
See the attachment below for full solution.
No, because an atom consists of two main parts and three subatomic particles - protons, neutrons, electrons. Each one is smaller than an atom, therefore they are subatomic particles. An atom only requires protons and electrons to be an atom - Hydrogen has 1 proton and 1 electron. Neutrons DO NOT affect the overall charge of the atom, and only increase the atomic mass.
Answer:
d. 37 °C
Explanation:
= mass of lump of metal = 250 g
= specific heat of lump of metal = 0.25 cal/g°C
= Initial temperature of lump of metal = 70 °C
= mass of water = 75 g
= specific heat of water = 1 cal/g°C
= Initial temperature of water = 20 °C
= mass of calorimeter = 500 g
= specific heat of calorimeter = 0.10 cal/g°C
= Initial temperature of calorimeter = 20 °C
= Final equilibrium temperature
Using conservation of heat
Heat lost by lump of metal = heat gained by water + heat gained by calorimeter

Power is the energy in a system per time. It will have units of Watts which is equal to joules per second. It can be expressed as:
P = E / t
where E = Force x distance
P = Fd / t
t = Fd / P
t = 8 (9.72) / 3.0
t = 25.92 s
The friction force is equal to the horizontal component of applied force 'p'. This horizontal component of force is pcosθ( θ = angle made by force with horizontal ).
Hence the frictional force is equal to pcosθ.