Answer:
The work done by friction was 
Explanation:
Given that,
Mass of car = 1000 kg
Initial speed of car =108 km/h =30 m/s
When the car is stop by brakes.
Then, final speed of car will be zero.
We need to calculate the work done by friction
Using formula of work done



Put the value of m and v



Hence, The work done by friction was 
The sunlight of all colors passes through air, the blue part causes charged particles to oscillate faster than does the red part. More of the sunlight entering the atmosphere is blue than violet, however, and our eyes are somewhat more sensitive to blue light than to violet light, so the sky appears blue.
Efficiency is completing a task as fast a possible the the least amount of effort.
Explanation:
It is given that,
When a high-energy proton or pion traveling near the speed of light collides with a nucleus, 
Speed of light, 
Let t is the time interval required for the strong interaction to occur. The speed is given by :




So, the time interval required for the strong interaction to occur is
. Hence, this is the required solution.
At the lowest point of its motion, kinetic energy is maximum and potential energy is minimum. This is where the velocity is a maximum. At the highest point of its motion, kinetic energy is minimum (i.e. zero) and potential energy is maximum.