Answer:
4N
Explanation:
a = (7-3)/5 = 0.8m/s^2
F = ma = (5)(0.8) = 4 Newtons
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.
Let's solve ~
Given terms :
The formula to find kinetic Energy is ~
Now, apply the formula according to given situation
Therefore, the kinetic Energy of the car is 56 joules
Answer:
18 m
Explanation:
Given : vo = 0 m/s ; t = 3 s; a = 4 m/s^2 ; d = ? m ; average velocity = ? m/s ; fonal velocity = ? m/s
solving for the final velocity, v
v = a * t
v = 4 m/s^2 * 3 s
v = 12 m / s
Solving for the average velocity. avg v
avg v = (vo + v) / 2
avg v = (0 m / s + 12 m/s) / 2
avg v = 6 m / s
Solving for the distance traveled after 3 s
d = avg v * t
d = 6 m / s * 3 s
d = 18 meters
In the first 3s the car travels 18 meters.
Answer:
a) variation of the energy is equal to the work of the friction force
b) W = Em_{f} -Em₀
, c) he conservation of mechanical energy
Explanation:
a) In an analysis of this problem we can use the energy law, where at the moment the mechanical energy is started it is totally potential, and at the lowest point it is totally kinetic, we can suppose two possibilities, that the friction is zero and therefore by equalizing the energy we set the velocity at the lowest point.
Another case is if the friction is different from zero and in this case the variation of the energy is equal to the work of the friction force, in value it will be lower than in the calculations.
b) the calluses that he would use are to hinder the worker's friction force and energy
W = Em_{f} -Em₀
N d = ½ m v² - m g (y₂-y₁)
y₂-y₁ = 35 -10 = 25m
c) if there is no friction, the physical principle is the conservation of mechanical energy
If there is friction, the principle is that the non-conservative work is equal to the variation of the energy
