An open vertical tube has water in it. A tuning fork vibrates over its mouth. As the
water level is lowered in the tube, a resonance
is heard when the water level is 30 cm below
the top of the tube, and again after the water
level is 50 cm below the top of the tube a
resonance is heard.
What is the frequency of the tuning fork?
The speed of sound in air is 343 m/s.
Answer in units of Hz.

How many nodes are in the tube after the
water has reached the second distance from
the top of the tube?

the gas collects in coils that then becomes a liquid that then flows through the coils inside the refrigerator

i think the answer would be reserve.

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.

when two balls of the different masses are dropped from equal height, they reach the ground at the same time .this is because they experience the same acceleration.

the acceleration is independent of mass.

thus when they are dropped they will always maintain the same velocity and travel the same distance (neglect air resistance of course) at the same time.