<span>Lets call F the friction force which will act horizontally backwards.
As you are travelling at a constant velosity horizontally there is no overall resultant force in this direction.
ie. the force you pull with will be equal to the friction force resisting you. (you will initially have to have pulled with a greater force than the friction to get the suitcase moving)
the value of your force pulling is 60 cos26.9 (horizontally) - you should have learnt about resolving forces.
this must be equal to F
so
F=60cos26.9
F=53.5N
hope this helps you
please mark this as brainliest answer</span>
Explanation:
(D) i think there you go have a good day
working...
Sound wave needs medium to travel
as energy which travels in this wave is because of transfer from one particle to another particle
If there is no medium then energy can not be transferred and sound wave will not travel
so in vacuum we can not listen sound
similarly here air is removed it means there is no medium inside the jar to travel the sound and hence we can not hear it
Option B is correct
Without air, the sound waves cannot travel to the ear.
Answer:
434 Hz
Explanation:
According to the Doppler effect, when a source of a wave is moving towards an observer at rest, then the observer will observe an apparent frequency which is higher than the original frequency of the source.
In this situation, Tina is driving towards Rita. Tina is the source of the sound wave (the horn), while RIta is the observer. Since the original frequency of the sound is 400 Hz, Rita will hear a sound with a frequency higher than this value.
The only choice which is higher than 400 Hz is 434 Hz, so this is the frequency that Rita will hear.
Han emperors made ________ the official belief system of the state