Assuming that the object starts at rest, we know the following values:
distance = 25m
acceleration = 9.81m/s^2 [down]
initial velocity = 0m/s
we want to find final velocity and we don't know the time it took, so we will use the kinematics equation without time in it:
Velocity final^2 = velocity initial^2 + 2 × acceleration × distance
Filling everythint in, we have:
Vf^2 = 0^2 + (2)(-9.81)(-25)
The reason why the values are negative is because they are going in the negative direction
Vf^2 = 490.5
Take the square root of that
Final velocity = 22.15m/s which is answer c
Answer:
Just 3
Explanation:
I believe the other two are incorrect
Well basically in physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant, it is said to be conserved over time. This law means that energy can neither be created nor destroyed, it can only be transformed or transferred from one form to another.
Hope this helps (:
Answer:
A. friction is greatly reduced.
Explanation:
Maglev train runs on the principle of repulsion force due to magnetic field
here we know that magnetic field will apply force on the train which helps to levitate train in air
This is why it runs forward due to other component of magnetic force and hence it can run with high speed in air with least friction as there is no two surfaces in contact with each other
So here we can say that
Train run with very high speed due to least value of friction between two surfaces which moves relative to each other
so correct answer is
A. friction is greatly reduced.
