☰
Matter In Our Surroundings
Define uniform and non-uniform speeds.
Uniform speed:
When the speed of an object remains constant with time, that is it does not change in regular intervals of time, the speed is said to be uniform.
That, is if an object covers equal distances in equal intervals of time, the body is moving with a unifrom speed.
E.g., A cyclist is covering 5 km uniformly every 1 hour.
Non-uniform speed:
A body is said to be moving with non-uniform speed when an object covers unequal distances in equal inervals of time.
E.g., A soccer player moving in the football ground.
Sponsor Area
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 :
Sponsor Area
Sponsor Area