The poles don’t receive direct sunlight which is why they are colder than the tropics. Even during the summer the sun is low on the horizon.
Answer:
It is used in MRI because it does not damage cells
Radio waves are used for space research because they have very long wavelengths
Explanation:
Many parts of the electromagnetic spectrum are applied in clinical diagnosis and treatment of illnesses. However, these highly ionizing radiation damage cells and its dosage must be carefully managed to avoid creating radiation related health problems for the patients.
Radio waves can be used in MRI without issues because the energy of the radiation is not sufficient to cause damage to cells but is sufficient to provide images for the sake of medical diagnosis.
Secondly, radio waves have long wavelength. This property is suitable for long range
communication. Hence it can be used in space research
Work done is given by product of force and displacement due to that force
So here we will have
here we know that
Now work done is given as
so it will do 16 J work to move the box
Answer:
V{+7 + 1000
Explanation:
Because Y + 7 + (828 and Y X P + ()
Answer:
i) kinetic friction; ii) The friction force always acts in the opposite direction to the movement of the surface where friction exists.
Explanation:
Part i )
At that time the type of friction that exists is kinetic, as there is movement by the wheel. At the moment when the wheel remains in rest over the inclined plane, the friction force which would be used will be the static force.
Part ii)
The friction force always acts in the opposite direction to the movement of the surface where friction exists. It is not opposed to the sense of movement. In order for the wheel to rise on the inclined plane, it must turn to the right, that is to say in the clockwise direction, therefore the friction force must go in the opposite direction to the rotation of the wheel, that is to say, go in the opposite direction to the movement of the surface under friction effect, that is why it points in the same direction of displacement of the wheel.