Given that,
Mass of the stone, m = 400 g = 0.4 kg
Initial speed, u = 20 m/s
It is climbed to a height of 12 m.
To find,
The work done by the resistance force.
Solution,
Let v is the final speed. It can be calculated by using the conservation of energy.

Work done is equal to the change in kinetic energy. It can be given as follows :

So, the required work done is 32.99 J.
Answer:
energy is converted into mass
Explanation:
D) A gallon of gasoline definitely. Gas is like, if not a chemical. It will have the most.
~Silver
Answer:
lower
Explanation:
The lower the value of the coefficient of friction, the lower the resistance to sliding.
The coefficient of friction is the ratio of the frictional force and the normal force pressing two surfaces in contact together.
U =
U is the coefficient of friction
F is the frictional force
N is the normal force
We see that coefficient of friction is directly proportional to frictional force.
Here we will the speed of seagull which is v = 9 m/s
this is the speed of seagull when there is no effect of wind on it
now in part a)
if effect of wind is in opposite direction then it travels 6 km in 20 min
so the average speed is given by the ratio of total distance and total time


now since effect of wind is in opposite direction then we can say



Part b)
now if bird travels in the same direction of wind then we will have


now we can find the time to go back



Part c)
Total time of round trip when wind is present


now when there is no wind total time is given by


So due to wind time will be more