Explanation:
the persons in the train hears it at a lower pitch
Hello!
In a thermostat, the property of the bimetallic coil that allows it to contract and expand is that The two metals absorb different amounts of thermal energy.
This bimetallic coil is used to transform thermal energy into mechanical movement. Two metals with different thermal expansivity are joined together parallelly and the changes of temperature cause bending in different directions depending on if the temperature is rising or descending.
The differences in the thermal energy absorption of the two metals are the basis for the mechanism of this device.
( 1.05 x 10¹⁵ km ) x ( 1 LY / 9.5 x 10¹² km ) x ( 1 psc / 3.262 LY ) =
(1.05) / (9.5 x 3.262) x (km · LY · psc) / (km · LY) x (10¹⁵⁻¹²) =
(0.03388) x (psc) x (10³) =
33.88 parsecs
The locations of earthquakes support the theory of plate tectononics by the recorded happening are mostly on the outline of tectonic plates.
Answers:
a)
b)
Explanation:
a) Final angular velocity
:
Before solving this part, we have to stay clear that the angular momentum is conserved, since we are dealing with circular motion, then:
Hence:
(1)
Where:
is the initial moment of inertia of the system
is the initial angular velocity
is the final moment of inertia of the system
is the final angular velocity
But first, we have to find and :
(2)
(3)
Where:
is the student's moment of inertia
is the mass of each object
is the initial radius
is the final radius
Then:
(4)
(5)
Substituting the results of (4) and (5) in (1):
(6)
Finding :
(7) This is the final angular speed
b) Change in kinetic energy:
The rotational kinetic energy is defined as:
(8)
And the change in kinetic energy is:
(9)
Since we already calculated these values, we can solve (9):
(10)
Finally:
This is the change in kinetic energy