Answer:
Explanation:
As you start increasing the force on an object from 0 N it the object will stay at rest and at a certain magnitude of force the object will start moving. The friction acting on that object is known as limiting frictional force. The magnitude of this frictional force is equal to the force that we apply on the object as it just start to move.
It's important to note that the limiting frictional force is the largest frictional force act on that object in the above explained process. The dynamic frictional force ( the frictional force acting on an moving object.) is always less than the limiting frictional force.
Answer:
Air is a mixture of gases. Gas is a state of matter. Hence, air is matter.
Explanation:
See the attached file. It contains a table explaining the composition of air.
Answer:
I would like aliens if they exist
Explanation:
Gamma rays, x-rays, ultraviolet, infrared, microwaves and radio waves<span>. Together with visible light, all these </span>types<span> of radiation </span>make up<span> what we call the </span>electromagnetic spectrum<span> </span>
Answer : The correct option is, (d) 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.


where,
= specific heat of copper = 
= specific heat of water = 
= mass of copper = 120 g
= mass of water = 300 g
= final temperature of mixture = 
= initial temperature of copper = ?
= initial temperature of water =
Now put all the given values in the above formula, we get:


Therefore, the temperature of the kiln was, 