The period of any wave is the time it takes for its angle
to go from zero to 2pi .
The 'sin' function is a wave. The angle of this one is (8pi t).
When t=0, the angle is zero.
Wonderful.
Now, how long does it take for the angle to grow to 2pi ?
I*n other words, when is (8pi t) = 2pi ?
Divide each side by '2pi': . . . . . 4 t = 1
Divide each side by ' 4 ': . . . . . t = 1/4
And there you are. Every time 't' grows by 1/4, (8pi t) grows by 2pi.
So if you graph this simple harmonic motion described by 'd', you'll
see the graph wiggle up and down with a period of 1/4 .
Answer:
Work done is equal to 125.44 J
Explanation:
We have given mass of the student m = 80 kg
Distance moved d = 4 m
Acceleration due to gravity 
Coefficient of kinetic friction 
So normal force exerted by student 
We know that work done is equal to multiplication of force and distance
So work done 
Answer:
The maximum speed of car will be 20.5m/sec
Explanation:
We have given mass of car = 1100 kg
Radius of curve = 82.3 m
Static friction 
We have to find the maximum speed of car
We know that at maximum speed centripetal force will be equal to frictional force 

So the maximum speed of car will be 20.5m/sec
To solve this problem, we must basically count the total energy lost converting all the values given in the international system.
The energy loss is given by both 124KJ and 124food heats.
Since the energy conversion we know that 1 food calories is equal to 4,184J. So:

Therefore the total energy lost will be


Therefore the total energy lost to the surroindings in form of heat is 124.518kJ