Answer:
counting tree rings can indicate age
Explanation:
hope i helped at least a little bit :)
Answer:
1) The strength of the electromagnet increases → Place a magnetic core inside the coil of wire
2) The electromagnet turns off → Turn off the battery supply
3) The poles of the electromagnet reverse → Change the direction in which the current flows
Explanation:
when current passes through a coil it behaves a an electromagnet.
Magnetic field strength is given by
B = μ N I
N is no of turns and
I is the current through coil
μ is permeability of the medium or core in the coil.
1). Magnetic core increase permeability μ so it will strengthen magnetic field:
B = <u>μ</u> N I
2). When the battery turns off current becomes zeroi.e I=0
So B = μ N * 0
⇒ B = 0
so electromagnet turns off
3). Direction of magnetic field can be determine by right hand rule, i.e curl the fingers in the direction of current, thumb will point in the direction of north pole.
so changing current direction will change direction of magnetic field.
Answer:
For the first blank, the answer is decreases. For the second blank, the answer is increases. And finally for the third blank, the answer is decreases.
Explanation:
For the first blank, the answer is decreases. For the second blank, the answer is increases. And finally for the third blank, the answer is decreases.
When a liquid is cooled, the kinetic energy of the particles decreases. The force of attraction between the particles increases, the space between the particles decreases, and the matter changes its state to solid.
Answer:
a) The shear stress is 0.012
b) The shear stress is 0.0082
c) The total friction drag is 0.329 lbf
Explanation:
Given by the problem:
Length y plate = 2 ft
Width y plate = 10 ft
p = density = 1.938 slug/ft³
v = kinematic viscosity = 1.217x10⁻⁵ft²/s
Absolute viscosity = 2.359x10⁻⁵lbfs/ft²
a) The Reynold number is equal to:

The boundary layer thickness is equal to:
ft
The shear stress is equal to:

b) If the railing edge is 2 ft, the Reynold number is:

The boundary layer is equal to:

The sear stress is equal to:

c) The drag coefficient is equal to:

The friction drag is equal to:

Answer:
Number of revolutions=1.532 revolutions
Explanation:
Given data
Distance s=8.0 m
Angular speed a=1.2 rev/s
To find
Number of revolutions
Solution
From the equation of simple motion we not that

So for the number of revolutions she makes is given as
