The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?
No, the law of conservation of energy is not violated. The loss in potential energy appears as an equal gain in kinetic energy of the object. Hence, the law of conservation of energy remains conserved.
Give reason for the following observations.
Naphthalene balls disappear with time without leaving any solid.
Give reason for the following observations.
We can get the smell of perfume sitting several metres away.
What is the physical state of water at
a) 25°C
b)00C
c)1000C
What is the physical state of water at
0°C
What is the physical state of water at
100°C
Give two reasons to justify
Water at room temperature is a liquid.
Give two reasons to justify
An iron almirah is a solid at room temperature.
Why is ice at 273K more effective in cooling than water at the same temperature ?
What produces more severe burns, boiling water or steam ?
8. Name A, B, C, D, E and F in the following diagram showing state change :
Mock Test Series
