Answer:
So coefficient of kinetic friction will be equal to 0.4081
Explanation:
We have given mass of the block m = 0.5 kg
The spring is compressed by length x = 0.2 m
Spring constant of the sprig k = 100 N/m
Blocks moves a horizontal distance of s = 1 m
Work done in stretching the spring is equal to 
This energy will be equal to kinetic energy of the block
And this kinetic energy must be equal to work done by the frictional force
So 


So coefficient of kinetic friction will be equal to 0.4081
50 *15=750
work is force time distance times angle between both vectors
here the angle is 0.
Answer:
Option D
+2
Explanation:
We know that Calcium has 20 electrons and 20 protons. It lost two electrons, it has 20 protons, but only 18 electrons. This makes calcium a positive ion with a charge of +2.
Answer:
the displacement is zero and the distance is 100 meters
Explanation:
Answer:
21.85 C
Explanation:
mass of iron = 1.5 kg, initial temperature of iron, T1 = 500 C
mass of water = 20 kg, initial temperature of water, T2 = 18 C
let T be the equilibrium temperature.
Specific heat of iron = 449 J/kg C
specific heat of water = 4186 J/kg C
Use the principle of caloriemetry
heat lost by the hot body = heat gained by the cold body
mass of iron x specific heat of iron x decrease in temperature = mass of water x specific heat of water x increase in temperature
1.5 x 449 x (500 - T) = 20 x 4186 x (T - 18)
336750 - 673.5 T = 83720 T - 1506960
1843710 = 84393.5 T
T = 21.85 C