Given:
temperature at which the rod is measured= 25°
length of aluminium rod measured at 25°C= 1 meter
temperature at which the scale is correct= 0°C
Linear expansivity of steel= 12* 10^-6
linear expansivity of aluminum= 26* 10^-6
To find:
True length of rod at 25°C
Length of rod at 0°C
Solution:
Let the length of the aluminum and steel rod at 0°C be L0A and L0S respectively.
Length of the steel scale at 25°C , thermal expansion is:
LA25 = LA0(1+ (αS - αA)25)
LA0 = LA25/ (1+ (αS-αA)t)
LA0 = 100/ (1+ (12*10^-6 - 26*10^-6)25)
LA0 ≈ 100.05 cm at 0°C
2. Let the length at 25°C of the aluminium trod be LA25
The actual measure of aluminum rod at 25°C, will be
LA25 = 100 * (1+ 26* 10^-6*25)
LA25 ≈ 100.06 cm
Answer:
10m/s^2
Explanation:
Force = mass x acceleration
Acceleration = force/ mass
= 20000000/2000000
=10m/s^2
Fossil Fuels:
Coal and Oil
How they are formed:
Coal is formed from big plants, from a long time ago. When the big plants died, they formed layers at the bottom of swamps and the dirt began to pile up and it formed Coal.
Oil is a fossil fuel that has been formed from a large amount tiny plants and animals such as algae and zooplankton.
Answer:
Option 2. It cuts through all the other layers
Explanation:
Newer or younger rocks are usually formed from older rocks in the sense that older rocks are broken up, and their by product materials forming together to make younger rocks.
We can simply say that older rocks basically undergo recycling to form newer rocks.
Thus, looking at the given options,
For option 1, the newer rock cannot be crumpled while the others lie flat because it is the old one that is undergoing recycling and therefore the older one is the one that will be crumpled to give way for newer rocks. So it's not true.
For option 2, since they are from older rocks, they will clearly cut through the other layers of the old one because the old one will give way for the new one.
Option 3 is not true for the same reason given for option 1.
Option 4 is not true because there is no standard way in which it will be positioned