Atrombone has a variable length. when a musician blows into the mouthpiece and causes air in the tube of the horn to vibrate, the waves set up by the vibrations reflect back and forth in the horn to create standing waves. as the length of horn is made shorter, what happens to the frequency?
a) the frequency will increase or decrease depending on how hard the horn player blows.
b) the frequency will increase
c) the frequency will decrease
d) the frequency will increase or decrease depending on the diameter of the horn.
e) the frequency will remain same

B) The frequency will increase

Explanation:

The length of the instrument is given by

Wavelength is given by

It can be seen that the length is inversely proportional to the frequency.

Here, the length of the trombone is decreasing so the frequency will increase.

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

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