Answer:
Emec = 94050 [J]
Explanation:
In order to solve this problem, we must understand that all thermal energy is converted into mechanical energy.
The thermal energy can be calculated by means of the following expression.

where:
Q = heat [J]
Cp = specific heat of water = 4186 [J/kg*°C]
m = mass = 300 [g] = 0.3 [kg]
T_final = 95 [°C]
T_initial = 20 [°C]
Now we can calculate the heat, replacing the given values:
![Q=0.3*4180*(95-20)\\Q= 94050[J]](https://tex.z-dn.net/?f=Q%3D0.3%2A4180%2A%2895-20%29%5C%5CQ%3D%2094050%5BJ%5D)
Since all this energy must come from the mechanical energy delivered by the exercise bike, and no energy is lost during the process, the mechanical energy must be equal to the thermal energy.
![Q=E_{mec}\\E_{mec}=94050[J]](https://tex.z-dn.net/?f=Q%3DE_%7Bmec%7D%5C%5CE_%7Bmec%7D%3D94050%5BJ%5D)
Friction force is equal to the applied force F until the block starts moving. Hence, it will increase until the maximum value of 3.0*10*0.50=150 N.
While it's moving, the friction will be 3.0*10*0.2 = 60 N, constant. The rest of the applied force will accelerate the block.
Answer:
The electromagnetic spectrum includes, from longest wavelength to shortest: radio waves, microwaves, infrared, optical, ultraviolet, X-rays, and gamma-rays.
As we know that mass of the iron will remain same in solid state as well as in molten state as per mass conservation theory
Now we can say

since mass is the product of volume and density so we can say

now from above equation we have

now by solving above equation we have


so final volume after it get solidify will become 175 cm^3
Answer:
Power brake is a device in vehicles which assists in braking by reducing the effort/force needed to apply the brakes on the pedal.