Explanation:
Given that,
A ball is tossed straight up with an initial speed of 30 m/s
We need to find the height it will go and the time it takes in the air.
At its maximum height, its final speed, v = 0 and it will move under the action of gravity. Using equation of motion :
v = u +at
Here, a = -g
v = u -gt
i.e. u = gt

So, the time for upward motion is 3.06 seconds. It means that it will in air for 3.06×2 = 6.12 seconds
Let d is the maximum distance covered by it.

Putting all values

Hence, it will go to a height of 45.91 m and it will in the air for 6.12 seconds.
Ans: Time <span>taken by a pulse to travel from one support to the other
= 0.348s</span>
Explanation:First you need to find out the speed of the wave.
Since
Speed = v =

Where
T = Tension in the cord = 150N
μ = Mass per unit length = mass/Length = 0.65/28 = 0.0232 kg/m
So
v =

= 80.41 m/s
Now the time-taken by the wave = t = Length/speed = 28/80.41=
0.348s
Answer:
if you mean *responsible* for the transport of water from the roots to leaves is Xylem
Here we have to calculate the number of rotations made by earth around its own axis in the entire life time of a human being.
The average human life is 50 years .
Each year is 365.5 days
Hence 
=18,275 days
The earth rotates around its own axis in 23 hours 56 minutes and 4 second which is approximately equal to 24 hours or one days.
Hence one rotation takes one days.
⇒18,275 days =18,275 rotations
Hence the total number of rotations made by earth around its own axis in the life time of a average human life time will be 18,275 times
Yes It is all metal is a good heat conductor