According to the Law of Conservation of Energy, energy is neither created nor destroyed. They are just transferred from one system to another. To obey this law, the energy of the substances inside the container must be equal to the substance added to it. The energy is in the form of heat. There can be two types of heat energy: latent heat and sensible heat. Sensible heat is energy added or removed when a substance changes in temperature. Latent heat is the energy added or removed at a constant temperature during a phase change. Since there is no mention of phase change, we assume the heat involved here is sensible heat. The equation for sensible heat is:
H = mCpΔT
where
m is the mass of the substance
Cp is the specific heat of a certain type of material or substance
ΔT is the change in temperature.
So the law of conservation of heat tells that:
Sensible heat of Z + Sensible heat of container = Sensible heat of X
Since we have no idea what these substances are, there is no way of knowing the Cp. We can't proceed with the calculations. So, we can only assume that in the duration of 15 minutes, the whole system achieves equilibrium. Therefore, the equilibrium temperature of the system is equal to 32°C. The answer is C.
Answer: The correct answer is option (C).
Explanation:
Law of reflection:
- Angle of incident is equal to angle of reflection;∠i=∠r
- Incident ray, reflected ray and normal to the reflecting interface at the point of incidence all lie in same plane.
When light ray from candle strikes a mirror at an angle of 40° with the normal, then the angle at which ray reflected back will 40°.
The answer is c 5 starrrrrr
Answer:
Explanation:
Absolute zero in the Kelvin scale = -273.15 °C
Temperature difference in the boiling and freezing point
Change in 21.5°C = Change of 100°C in M
Difference in the Celsius scale
Change in 
corresponds to
Therefore the absolute zero in the Methane scale is
If the collision is elastic, there is no loss in kinetic energies, which means that the total energies before and after impact are the same. So no need to worry about final velocities.
Final energy
= initial energy
= (1/2) (7.20*2.00^2+5.75*(-1.30)^2)
=19.26 joules
Answer: the total kinetic energy is 19.3 J. after collision.
