French Physicist Leon Foucault introduced his pendulum in 1851.
By that time, it was generally accepted that the Earth rotates, but
Foucault's pendulum was the first simple demonstration that made
the Earth's <u>rotation</u> easy to prove.
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.
Answer:
distance changing at rate of 3.94 inches/sec
Explanation:
Given data
wall decreasing at a rate = 9 inches per second
ladder L = 152 inches
distance h = 61 inches
to find out
how fast is the distance changing
solution
we know that
h² + b² = L² ..................1
h² + b² = 152²
Apply here derivative w.r.t. time
2h dh/dt + 2b db/dt = 0
h dh/dt + b db/dt = 0
db/dt = - h/b × dh/dt .............2
and
we know
h = 61
so h² + b² = L²
61² + b² = 152²
b² = 19383
so b = 139.223
and we know dh/dt = -9 inch/sec
so from equation 2
db/dt = -61/139.223 (-9)
so
db/dt = 3.94 inches/sec
distance changing at rate of 3.94 inches/sec
Answer:
A. 1.6 N/cm
Explanation:
spring constant = 21/13 = 1.6 N/cm
