An opera singer in a convertible sings a note at 700 Hz while cruising down the highway at 90 km/h . The speed of sound in the air is 343 m/s. 1. What is the frequency heard by a person standing beside the road in front of the car?
2. What is the frequency heard by a person standing beside the road behind the car?

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards