A bowl-shaped depression formed by a mountain glacier is termed a cirque.
Momentum = (mass) x (speed)
Mass is constant, so the rate of change of momentum is
(mass) x (rate of change of speed) .
But (rate of change of speed ) is just acceleration.
So the rate of change of momentum is (mass) x (acceleration).
But (mass) x (acceleration) is Force.
So Force is the rate of change of momentum. Verrrrrrrry interesting !
In this problem, Force = (40 kg) x (9 m/s²) = 360 newtons.
One 'Newton' is one kilogram-meter per second² .
Unit of momentum is (kilogram)-(meter per second), so 'newton'
is also a unit of time rate of change of momentum.
Rate of change of momentum is 360 momentum units per second.
The chemical formular for water is H2O.
The H aspect of the formula stands for hydrogen gas and the subscript 2 which is attached to the H symbol signifies that two atoms of hydrogen are joined together, that is two atom of hydrogen are present.
The chemical formula of water indicates that, two atom of hydrogen react with one atom of oxygen to form one molecule of water.
In chemical formulae, subscripts are normally used to indicate the number of atoms that are present in a molecule.
Which amplitude of the following longitudinal waves has the greatest energy?
amplitude = 10 cm; wavelength = 6 cm; period = 4 seconds
First of all, we need to calculate the work done by the forklift to lift the box of 500 kg by 4 meters. The work done is equal to the variation of gravitational potential energy of the box, given by:
where m=500 kg is the mass of the box,
and
is the variation of height of the box. Substituting these data into the equation, we find the work
And now we can calculate the minimum power required by the forklift, which is equal to the ratio between the work done and the time taken:
