Answer:
hi, the reason is for friction so that they don't fall. subscribe to me on you tube. name is my brainly name
Explanation:
Answer: Neon is a colorless gas at room temperature: Physical property
At room temperature, mercury is a liquid: Physical property
Apple slices turn brown when exposed to air: Chemical property
Phosphorus will ignite when exposed to air: Chemical property
Explanation:
Physical property is defined as the property of a substance which becomes evident during physical change in which there is alteration in shape, size etc. No new substance gets formed during physical change.
Example: Neon is a colorless gas at room temperature
At room temperature, mercury is a liquid.
Chemical property is defined as the property of a substance which becomes evident during chemical change in which a change in chemical composition takes place. A new substance is formed in these reactions.
Example: Apple slices turn brown when exposed to air: It undergoes oxidation which is a chemical change
Phosphorus will ignite when exposed to air: It undergoes oxidation which is a chemical change
Explanation:
It is given that,
Length of the helicopter, l = 3.1 m
The helicopter rotates, the length of helicopter will become the radius of circular path, r = 3.1 m
Angular speed of the helicopter, 
(a) The centripetal acceleration in terms of angular velocity is given by :



(b) Let v is the linear speed of the tip. The relation between the linear and angular speed is given by :


v = 90.89 m/s

Hence, this is the required solution.
Answer:
32 m/s
Explanation:
The speed of a bus is 30 m/s due East wrt the passenger
He also sees a passenger on the bus walking to the back at 2 m/s.
We need to find the passenger's velocity relative to the bus. As the observer sees that the bus and the passenger are moving in opposite direction. Let v is the relative velocity. So,
v = 30 m/s + 2 m/s
v = 32 m/s
Hence, the passenger's velocity relative to the bus is 32 m/s.
Answer: The rate at which water moves through the plants due to transpiration plays an important role in maintaining plant water balance. ... This moves water and other nutrients absorbed by roots to the shoots and other parts of the plant. Hence, transpiration is very important for the survival and productivity of plants.
Explanation: the explanation of the answers is that Advantages of a dry cell are:
The compact size of a dry cell makes it suitable for powering small electronic devices.(toys, flashlights, portable radios, cameras, hearing aids). The electrolyte used in dry cell is relatively not so harmful to the environment. Dry cells are inexpensive. The main disadvantage of a dry cell is that it cannot be recharged once it loses its electrical power, Because when the cells turn any color then you are died.