The needle, when playing a gramophone record, presses on it with a force of 0.3N.

The needle, when playing a gramophone record, presses on it with a force of 0.3N. What pressure does the needle exert if the area of its tip is 0.0003 cm2.

Given:

F = 0.3 Newton – the force with which the needle presses on the record when playing;

s = 0.0003 square centimeters – the area of ​​the needle tip.

It is required to determine P (Pascal) – the pressure with which the needle presses on the record.

We convert the units of measurement of area from square centimeters to square meters:

s = 0.0003 cm2 = 0.0003 * 10 ^ -4 = 3 * 10 ^ -4 * 10 ^ -4 = 3 * 10 ^ -8 square meters.

Then, to determine the pressure, you must use the following formula:

F = P * s, from here we find that:

P = F / s = 0.3 / (3 (10 ^ -8) = 0.1 * 10 ^ 8 = 10 ^ 7 Pascal = 10 MPa.

Answer: the pressure of the needle on the gramophone record is 10 MPa.